the world in which he exists

Days passed by, the new semester was coming, and it was the day when I could see Lin Jianfan every day. Before leaving school for a while, Gu Chaoming had already started preparing for the start of school, and began to wait to meet Lin Jianfan.

Gu Chaoming likes school. He used to like school because it was his paradise, a place where he could stay away from Gu Tao.Now Gu Chaoming also likes school, but the reason why he likes school is that he can meet Lin Jianfan.

The start of school that Gu Chaoming has been preparing for for a long time is finally coming.A week before the start of school, Gu Chaoming even thought about which clothes to wear from the start of the journal, and waited anxiously.

Throughout the winter vacation, I was looking forward to meeting Lin Jianfan. When I didn’t meet, I was looking forward to meeting, and after meeting, I was looking forward to the next meeting.

From the beginning of the journal to the early morning of the day, Gu Chaoming was still chatting with Lin Jianfan on the way to school.

Many students returned to the campus almost a month later, their youthful exuberance mixed with the melancholy of just starting school.

For the extra excitement of the start of school, Gu Chaoming is really the only one in the school.

Looking at the familiar campus, Gu Chaoming took the wind under his feet and quickly walked through the aisle that the school must pass through every morning.

Arriving at the downstairs of the teaching building, the teaching building has resumed the bustling start of school after the winter vacation. There are people coming and going in the corridor, and there are people going up and down in the stairs.

Not seeing each other for almost half a month, Gu Chaoming took advantage of his fast running, avoided the crowd on the stairs, and rushed straight to the floor where his class was located.

so looking forward to it.

Gu Chaoming knew that he was looking forward to it, but he ran upstairs uncontrollably, which was still beyond his expectation.

It turned out that he had only seen him for half a month, and he already wanted to see him so much beyond his expectations.

Expectations are always accompanied by fantasies.During the day and night before school starts, Gu Chaoming always imagines what it would be like to meet Lin Jianfan on the first day of school.

Lin saw that Fan might sit quietly and talk to Li Zhao, which was the possibility that Gu Chaoming had thought about the most.

But he didn't expect that on the first day of school, he couldn't help "touching" Lin Jianfan with his eyes.

Gu Chaoming underestimated his expectation of seeing Lin Jianfan, and also underestimated Lin Jianfan's temptation to him.

Gu Chaoming, who rushed up the teaching building, trotted to the front of his class. As soon as he entered the door, the soles of his shoes had just stepped on the floor of the second and second class of high school. His waist, which was not covered by clothes, made him stop, and he couldn't help swallowing Next saliva.

Gu Chaoming by the door of the classroom stood still in place, staring at Lin Jianfan's waist exposed because he took the clock on the blackboard and stretched his cotton clothes to pull it upward.

Hearing the noise of his classmates who hadn't seen him for a month, Gu Chaoming came back to his senses, hoping that his out-of-the-ordinary eyesight would not be noticed by his classmates.

Lin Jianfan was surrounded by two girls, one was crying bag Shi Cancan, and the other was Shi Cancan's good friend.Gu Chaoming looked away again, and there was still a chair on the desk.

Surrounded by Lin Jianfan's girl changing batteries and the chairs on the podium, Gu Chaoming successfully restored the scene before he came.

Lin saw that Fan Ding saw Shi Cancan move the chair to change the battery, and saw that Shi Cancan was petite, so he came up to help her.

Thinking of this, Gu Chaoming glanced at Li Zhao's place as he walked towards the podium, but there was no one there.

Li Zhao, oh Li Zhao, I told you to come late, you didn't come to grab such a good opportunity earlier.

"Morning, how about changing the battery?" Gu Chaoming walked over and said.

After changing the battery cover, Gailin saw Fan Wensheng looking towards Gu Chaoming.

Lin Jianfan nodded.

Gu Chaoming stopped beside Lin Jianfan, and couldn't help but slide his gaze down to the waist where Lin Jianfan put down his arms and was covered by cotton clothes.

It only showed a little bit, so Gu Chaoming stared at it for a while.

Dirty, Gu Chaoming looked at Lin Jianfan's waist and felt that he was filthy.A 17-year-old boy always applies ugly and dirty words to himself for some reason.

Dirty thoughts, licking arms, and all dirty actions are targeted at Lin Jianfan.

Seeing Lin Jianfan's bare waist, Gu Chaoming stood at the door of the classroom and thought that Lin Jianfan's waist was so pretty, fair and sharp, making him want to grab it.

Realizing his own thoughts, Gu Chaoming's train whistled in his mind and stopped immediately.

What are you thinking, it's really nasty.

Gu Chaoming, who harbored dirty thoughts, took the clock that Lin Jianfan had set the time and replaced the batteries without making a sound, and turned around to help him hang it on the blackboard.

Li Zhaolai was one step behind. When Gu Chaoming helped Lin Jianfan hang up the clock and walked down from the podium, Su Bing happened to walk in with Li Zhao from the door of the classroom. As soon as Li Zhao came in, he saw Shi Cancan on the podium. .

Su Bing didn't see Gu Chaoming helping Lin Jianfan hang the clock, but when he came to the school, he saw Gu Chaoming and Lin Jianfan walking off the podium together.

Why did Gu Shuai seem to have become stupid?Su Bing looked at Gu Chaoming who was smiling and chatting with Lin Jianfan as he walked off the podium.

Li Zhao beside him also looked at Shi Cancan without blinking.

Su Bing deeply felt that he was surrounded by a group of school-starting hormones, and he did not know how many times he began to miss his ally Cen Xili.

"Xili, come quickly, someone abused me." Su Bing cried inwardly.

"Why hasn't Xili come today?" Su Bing asked Gu Chaoming.

Gu Chaoming shook his head: "Why don't you send him a message? Lao Chen hasn't come to the classroom yet, what are you in a hurry for?"

Su Bing went back to his seat and sent Cen Xili a message asking him where he was, but he hadn't received a reply yet, and Lao Chen, who Gu Chaoming said hadn't come yet, walked into the classroom.

"Ahem," Lao Chen coughed twice with his hands behind his back to signal for silence, "Is it all here?"

Looking around at the empty tables under the podium, it seems that there are still a few people who haven't arrived.

"Are you late at the beginning of school? The class monitor calls down names to see who hasn't arrived yet."

Speaking of roll call, Gu Chaoming looked at the empty table next to him. Old Chen set a check-in time, and Cen Xili, who was usually not late, was late today.

It was just a report, old Chen should be fine, Gu Chaoming called Su Bing softly from the air, and asked if Cen Xili had replied to his message.

Su Bing shook his head and spread his hands, saying no.

Su Bing did not receive Cen Xili's reply, and Gu Chaoming also sent a message asking where Cen Xili was.

"Report." A loud report at the door abruptly pulled Gu Chaoming's attention to the classroom door.

Liu Guangyu was panting heavily at the door of the classroom, apparently after running past.

Old Chen stood on the podium and turned his head to look out the door, raised his chin to signal Liu Guangyu to come in.

Not long after Liu Guangyu entered the classroom, the monitor reported that only Wu Shan and Cen Xili were left.

Hearing these two names linked together, Gu Chaoming couldn't help thinking that Wu Shan would be the one who made trouble for Xili as soon as he started school, right?

Gu Chaoming was always afraid of being bullied for Cen Xili's temperament of holding back his anger and keeping silent, and that one thing more is worse than one thing less.If Wu Shan really dares to embarrass Cen Xili, let's see if he doesn't knock out all of Wu Shan's front teeth.

Thinking of Wu Shan's bullying, Gu Chaoming took another look at Lin Jianfan's position, and by the way, Yu Hangwei at Lin Jianfan's front desk.

Since Yu Hangwei was beaten last time, he has become much more honest. Kai Xue and Lin Jianfan didn't say a word, pretending not to know each other.

Gu Chaoming was worried that Cen Xili would be bullied by Wu Shan on the road. Wu Shan bullied the weak and was afraid of the strong. Wu Shan dared to be rampant when they were not around, but after a while, Wu Shan hurried into the classroom as if he was late.

Lao Chen let him in without saying anything.

Old Chen was about to finish his long-winded words, but Cen Xili hadn't come yet.

Cen Xili did not reply to the message sent by Gu Chaoming. While Lao Chen walked to the corridor to call Cen Xili's parents, Gu Chaoming asked Su Bing again if Cen Xili had replied to his message.

Su Bing shook his head again, no.

Seeing that Fan turned his head, Lin in the front saw Su Bing and Gu Chaoming worried, and asked, "Will Xili not reply to your message?"

Su Bing nodded while typing.

Gu Chaoming, who gradually began to worry, looked at Wu Shan who was sitting in the seat with unfavorable eyes, and Wu Shan looked at Gu Chaoming in a daze.

When did I offend him again?Wu Shan thought to Gu Chaoming's eyes.

Seeing Wu Shan's expression of not knowing what happened, Gu Chaoming turned his gaze away and let him go.

He didn't reply to the news, and he couldn't make a phone call now. Gu Chaoming even wanted to ask You Xin from the science class, did he take Cen Xili away?

I don't have You Xin's contact information. I used to have it when I was in a class, but Gu Chaoming deleted it after the quarrel.

Gu Chaoming added You Xin through the previous class, and You Xin immediately asked Gu Chaoming what was the matter, and Gu Chaoming would not add him if there was nothing wrong.Gu Chaoming was also unambiguous, and asked him if he was with Cen Xili.

You Xin, who was cleaning up in class, frowned. He hadn't seen Cen Xili today, didn't Cen Xili come?You Xin stopped mopping the floor, typed rapidly with fingers holding the mop handle, and asked Gu Chaoming, "What's wrong with Cen Xili?"

Knowing that Cen Xili wasn't with him, Gu Chaoming didn't want to reply him anymore, but was afraid that You Xin would lie, so he asked, "Is it true that I wasn't with you?"

You Xin took a photo of a mop in his hand and sent it to Gu Chaoming: "I was doing hygiene in class, and Xi Li is really not here."

After posting, You Xin asked worriedly, "What's wrong with him? Didn't come today?"

Gu Chaoming did not reply.

If he wasn't with You Xin, where did he go?Nothing will happen, right?

Old Chen in the corridor was still on the phone, Gu Chaoming sneaked to the open back door, and lay on the door frame to eavesdrop on Lao Chen's phone call.

Hearing old Chen say "don't worry" and "the child may just be late", it seems that Cen Xili's family doesn't know where he is.

The family doesn't know?runaway?No way?Gu Chaoming guessed that Cen Xili was not so reckless.

"He just got up a little late today and went out by bike, so there will be no accidents on the road???" Mama Cen said anxiously on the phone.

"He hasn't come to school yet, I will call you first when he comes..."

Lao Chen hung up the phone and walked into the classroom with an obviously heavy expression.

Gu Chaoming just wanted to make a call to Cen Xili, but Lao Chen was in the classroom again.

At this time, You Xin, who was mopping the floor in the science class, was waiting for Gu Chaoming's reply. Gu Chaoming didn't reply for a long time, so You Xin couldn't help but click on the contact person to call Cen Xili.

There was a ring, but no one answered.

Another hit is still the same.

You Xin made several calls, and You Xin didn't know that Cen Xili's cell phone was in the sewer by the side of the road, but no one answered it.

Bells rang in the sewers, phone screens lit up in the sewage.

The owner of the mobile phone has not yet realized that his mobile phone has disappeared.

Cen Xili got up late on the first day of registration, quickly packed up his bike and went out, stepped on the pedal faster while checking the time to avoid being late.

The wind in winter before the beginning of spring was a bit cold, Cen Xili forgot to wear gloves when he was in a hurry to go out, his fingers holding the handlebar of the car were blown cold by the wind, and his nose was also red from the cold wind.

Cen Xili accelerated his speed and paid attention to the road conditions, when a motorcycle racing behind him suddenly passed him quickly and knocked him down to the side of the road.

Fortunately, Cen Xili didn't hit directly, but because the two cars were too close, they brushed, and Cen Xili's bicycle fell to the side of the road.

In a hurry, Cen Xili tried to step on the ground to prevent his fall, but found that it was futile. The resistance under his feet made him go straight to the bushes on both sides of the road. The wheel turned, and he fell into the side of the road together with the car in the bushes.

After falling down, he felt a sharp pain in his left leg, and rushed face first into the bushes. Without looking in the mirror, Cen Xili knew that his face must have been scratched by the bushes just by the slight pain on his face.The bicycle pressed my foot, and the pain in my left leg directly overwhelmed the pain in other parts of my body.

Cen Xili pushed the bicycle away from his legs, and passers-by helped him up and asked him how he was doing.

Cen Xili stood on one leg, his left leg hurt so badly that he couldn't touch the ground, a kind person helped him to lift the bicycle up, and Cen Xili thanked him.

The person who hit him with his bike was quite conscientious, he thought he would run away, but who would have thought that he would come back after a round of riding, and stop in front of Cen Xili who was standing on one leg, taking off his helmet.

"How are you?" the man asked holding his helmet.

Seeing the scratch on Cen Xili's face: "Oh, it doesn't look like it's okay."

The passer-by who was helping saw that the kid on the bike had a bad attitude, so he advised him: "The young man was the one you bumped into, right? Don't ask if it's okay, take him to the hospital for a checkup first."

The passers-by who helped him called him a young man, because the young man who hit people looked so young that people doubted whether he had a driver's license.

The passers-by who helped him had a sense of justice. The boy who was afraid of bumping into someone was the kind of gangster in society who wanted to repay his debts, and the boy who got bumped looked like a good student, and he was still wearing a school uniform.

Passers-by saw it right, but they only saw Cen Xili right.Cen Xili is a good student, but the young man who bumped into him was not a social bastard, and he had no intention of running away.

The racing boy squatted down, saw that Cen Xili's left foot seemed to be in pain, and squeezed Cen Xili's injured left foot.

Cen Xili was pinched in pain, he hissed, and retracted his legs.The pain in his legs and the boy's playful behavior made Cen Xili lose his usual good temper, and he retracted his legs and gave the boy who pinched him a hard look.

The racing boy smiled crookedly. Seeing that Cen Xili retracted his foot in pain, he stretched out his hand and pinched it as a mischief.

Cen Xili frowned, not because he was pinched and hurt by the young man, but because he felt that this person was like this?He obviously caused others to fall, but he didn't say sorry, knowing that he was injured, pinching his leg once was not enough, so he continued to pinch it.

Cen Xili glared at him again, the racing boy didn't care about his injuries, instead he smiled and said, "You stare like a little wild cat."

Because he found that Cen Xili stared at him like a little wild cat, the racing boy wanted to see him again, so he pinched him twice.

The drag racing boy stood up, patted his hands wearing black leather gloves, and was fully equipped for drag racing.

From the first time he saw him, Cen Xili had already categorized him as a ghost boy or a non-mainstream.

If he knew that Cen Xili saw him this way, the drag racing boy would talk to him unreasonably: "What is a will-o'-the-wisp boy? Why are you just like my dad at a young age? I am a drag racing enthusiast, and I am going to participate in competitions in the future. understand?"

The racing boy glanced at Cen Xili, and asked flatly, "Can I still go?"

Cen Xili tried it, but his left foot hurt after taking a step, and he couldn't walk at all, so he shook his head.The racing boy watched and sighed, and asked Cen Xili to lock the bike.

Cen Xili couldn't move his legs at all, he could only jump around with his right leg, and he had to bend over and squat down to lock the bicycle. Seeing that Cen Xili was not moving very smoothly, the racing boy went to his bicycle and helped him lock the bicycle.

After locking the bicycle, the drag racing boy thanked the passer-by who helped, and the passer-by said, "It's okay, but you don't ride a bicycle in the future."

"Got it, got it." The racing boy said.

Cen Xili stood there with a limp, and the racing boy walked up to his car and shook his head at him: "Come up, I'll take you to the hospital."

"You won't be able to leave because you hurt your leg?" Seeing that Cen Xili was not moving, the racing boy walked back to Cen Xili from the front of the car and asked.

Cen Xili sighed, obviously unhappy and said: "Yes."

Jumping towards the boy's car like a kangaroo on one leg, only to be laughed at by the boy?

Cen Xili frowned rarely, the boy burst into laughter, Cen Xili glared at him: "What are you laughing at?"

"Hey, don't be angry." The racing boy said with a smile.

Cen Xili sighed again, complaining that he was so unlucky to meet such a person.

Still complaining, his body lightened, and he was hugged by someone horizontally.Cen Xili's body was suspended in the air, his heart stopped, and he was startled.

"What are you doing?!" Cen Xili, who was being carried sideways, shouted.

The racing boy hugged the struggling Cen Xili and said, "Don't move around, I'll carry you into the car, little kangaroo."

Being forced into the car, Cen Xili experienced the first drag racing in his life.Feeling bad, without a helmet he arrived at the hospital with his hair blown like a bird's nest.

The boy laughed at him again, and Cen Xili was in a bad mood as he straightened his hair.

When he arrived at the hospital, the racing boy didn't rush to register, but made a phone call first. Cen Xili stood aside and listened to their conversation, and found that his father might still be a doctor.

Are doctors' sons prone to rebellion?Cen Xili stood aside and thought.

His guess was right. He healed his leg, put a cast on his foot, and walked on crutches. When he walked to the hospital corridor, he saw the racing boy being reprimanded by a doctor in a white coat.

The racing boy leaned against the wall of the hospital, with a look of "I don't care, you continue to talk".

Seeing Cen Xili walking over with a cane, the racing boy couldn't help laughing.

"What are you laughing at, you can still laugh when you bump into someone?" The doctor yelled at the hospital paying attention to the volume.

The racing boy looked at Cen Xili and said to his father, "Here comes the person who got hit."

The doctor turned his head and saw Cen Xili approaching with a cane, and hurried over to apologize to him: "I'm sorry, I'm sorry, I'm Guan Hui's father, and I'm also the doctor here, I'm really sorry for bumping into you."

Cen Xili hurriedly said, "It's all right."

"Everyone said it's all right." Said the racing boy leaning against the wall.

The doctor turned his face to face his son and had a completely different expression to the injured Cen Xili.

The racing boy turned his face away.

"Don't worry, we will cover all the medical expenses," the doctor saw the school uniform on Cen Xili's body, and found that Cen Xili and his son belonged to the same school.

"Guan Hui, are you alumni?" The doctor turned his head and asked his son.

"You just found out?" The racing boy rolled his eyes. When he saw his school uniform while driving behind Cen Xili, he knew that Cen Xili belonged to his school.

The way these two father and son get along, Cen Xili can't seem to say anything.

"After that, you can take care of others more," the doctor said to his son, then asked Cen Xili's high school, what his name was, and which class he was in.

Knowing that Cen Xili's name is Cen Xili, he was a sophomore in high school, and after the second class, the doctor said to his son, "It's your senior, why don't you come over to apologize to me?"

The racing boy named Guan Hui refused: "What senior, I'm 17 too, okay? I can't study late."

"Look at someone who is 17 years old, and then look at you, like a child who doesn't understand anything." The doctor said.

"When is your birthday?" Guan Hui asked Cen Xili.

"What are you doing?" Cen Xili was very defensive towards this bad-ass racing boy.In the impression of Gu Chaoming and Su Bing, Cen Xili has always been gentle with others, and the person who can make Cen Xili so defensive, Gu Chaoming and Su Bing did not expect that they would actually meet him.

"Just ask." The racing boy said.

"It's okay, he just has this temper, and he doesn't know what to do." The doctor explained.

Only then did Cen Xili hesitate to answer: "April 23."

"Hahahaha..." The racing boy suddenly laughed in the hospital, "I'm September [-]rd, isn't it natural that you are older than me and a bit more mature?"

So that's where he asked about his birthday? ? ?

Cen Xili looked like you were kidding me.

Seeing his disobedient son, the doctor couldn't help but sigh: "He's like this, kid's temper, don't worry about him, don't you guys start school today? Are you in a hurry? Anyway, he is not in a hurry, do you want to inform him? Home and school?"

Cen Xili didn't know that Lao Chen and Gu Chaoming were looking for him at school. Cen Xili wanted to call Lao Chen, and took out his school uniform pocket, but found that the pocket was empty and contained nothing.

Where's the phone?Cen Xili searched both pockets, but found none.

"Are you looking for your mobile phone?" the racing boy asked, "Your mobile phone fell into the sewer when it fell down. If your mobile phone is of good quality, it may still be useful to call the fire department to retrieve it now, but it smells a little bit."

Cen Xili looked at him unreasonably.

The doctor was worried about his son: "Did you lose your phone? Guan Hui, you pay for the compensation yourself and the medical expenses. Don't expect me to pay for the phone."

"Cut," Guan Hui said disdainfully, "If you pay, I'll let grandma take the money."

The doctor hates iron but not steel: "You know how to ask grandma to take the money. If grandma doesn't give you the money, I don't think you can drink Northwest Wind."

Cen Xili stood there quite speechless, saying that he didn't need it, but no matter how he shirked it, the doctor insisted on returning his son and letting his son take good care of him.

"What class are you in?" The doctor turned to his son.

"You don't know what class I'm in, but you're still my dad."

It is typical to feel that my father does not love me.

"Say it quickly." The doctor emphasized.

"Class 02, Senior [-], Guan Hui, desk [-] of Group [-], student number [-], head teacher Zhu Guangtou, deputy monitor of Class [-], I follow your orders," Guan Hui introduced himself in a drawn-out tone of disdain, and added a sentence at the end: "Okay? Can I go?"

"Where are you going? Take him back to school, and you go back to school for me," the doctor said.

"Cheng Chengcheng, please." Guan Hui walked up to Cen Xili with his pockets in his pocket and stretched out his hand in a gesture of invitation.

"Take good care of her. If she comes to complain, I won't beat you to death."

Before leaving, the doctor handed Cen Xili a business card: "Call me if this kid is disobedient, and I will teach him a lesson."

Completely different attitudes of father and son.

After walking out of the hospital, Guan Hui stopped a taxi, opened the door and let Cen Xili get in.

Guan Hui pulled the door and saw that Cen Xili would not go in: "What are you waiting for? You want me to hug you if you don't go in?"

"You don't drive anymore?" Cen Xili asked.

"Damn it, I hit you, do you think my dad will drive for me?" Guan Hui took Cen Xili's crutch under his armpit and pushed him into the car.

Cen Xili looked out the window and heard that what Guan Hui told the driver was not the address of the school, Cen Xili asked, "Where are you going if you don't go to school?"

"Take you to buy a mobile phone? Don't you want it? Don't pull it down." Guan Hui said, leaning on the back seat of the taxi.

After Cen Xili bought the mobile phone and changed to a calling card, he didn't know how long it had been.Cen Xili immediately called his family to tell them not to worry, and then called Lao Chen to explain.

When he boarded the chat software, he saw that Su Bing and Gu Chaoming replied to the messages sent to him one by one. Lin Jianfan also sent him messages, and Cen Xili replied one by one to report that he was safe.

After replying to all, there was only one person who was particularly concerned, and Cen Xili finally clicked on the chat interface with him.

They all asked him where he was, and when he saw the message and asked him to reply, Cen Xili slowly typed the three words "I'm fine" on the keyboard.

The other person replied immediately, and Guan Hui leaned back in his chair and suddenly said, "You Xin from the basketball team in the sophomore year?"

After replying to You Xin's message, Cen Xili said to Guan Hui, "Didn't anyone tell you not to peek at other people's phones?"

"I didn't peek," Guan Hui turned his face away. He just turned his head to ask him "how do you feel?" and saw that he had been staring at the phone, and accidentally saw the word You Xin. Flashed by, definitely not intentionally peeking.

Cen Xili ignored him, and Guan Hui repeated again: "I didn't peek, I never peek at other people's mobile phones."

Cen Xili really didn't want to talk to him: "All right, all right, don't peek, brat."

"Little boy?" Guan Hui looked at Cen Xili who said he was a little boy in disbelief.In Guan Hui's world, calling him a kid is tantamount to scolding him.

I don't know if he was infected by Guan Hui after staying with Guan Hui all morning, Cen Xili also replied to him childishly: "You are younger than me, so you are not a brat?"

"I'm just a few months younger than you."

"You are still young for a few months, will you ask your seniors to hear?" Cen Xili said.

"Senior fart."

"If you don't call me senior, I'll call your father." Cen Xili threatened him with a doctor's business card.

"You look gentle, I didn't expect you to have so much bad water in your stomach." Guan Hui said that he wanted to grab the business card in Cen Xili's hand.

Cen Xili stopped: "I already know the name of the hospital your father is in. It's useless for you to take it away. I'll call or go to the hospital and ask."

"Are you called senior?" Cen Xili looked at Guan Hui proudly and asked.

Now Guan Hui had nothing to do with him, he gritted his teeth and shouted: "Learn, sir!"

"Good boy, that's right." Cen Xili stretched out his hand to touch Guan Hui's head and said with a smile.

Guan Hui was patted on the head and forced to call him a senior, so he leaned back in his chair angrily.

Cen Xi stood beside him and laughed at him.

Sure enough, childishness is contagious.