Have you ever rubbed your hands together when they get cold? Why do we do that? We do that for friction. Friction happens when two things that aren’t very smooth rub together to make heat energy. The faster you rub two things together, the more friction ( and heat) you can make. Let’s discover friction!

WHAT YOU’LL NEED

·Soap ·Water·Your hands!

WHAT TO DO

Make sure your hands are dirty.

Rub your hands together until you feel the heat of your hands.

Now, use soap and water to get your hands very slippery(滑的).

Try to make friction happen while your hands are slippery.

Please write down what has happened.

LET’S TALK!

Friction is an energy that happens when two things rub together. When friction happens, it makes heat! When your hands are slippery, they won’t make very much friction and your hands won’t get so hot.

DID YOU KNOW?

Friction happens when you stop your fast running bike.

Ancient people made fire by rubbing two pieces of wood together. Friction happened though they didn’t know it.

____?___

Friction is everywhere. Have you ever noticed situations where friction is happening? If not, ask your parents to take you out in a car. If it is not hot, touch the tires(轮胎) of the car before and after a short drive to see how much warmer they get from friction.

1. This text is most probably________________________.

A. a science report????????????? ????????????? ????????????? 　 B. a car advertisement

C. a rubbing introduction?????? D. a chemistry programme

2.What does the word “friction” in this text mean in Chinese????????

A.摩擦????????????? ????????????? B. 冷却??????? C. 膨胀????????????? ????????????? ????? D.震动

3.___________ is not an example of friction.

A. Bike riding????????????? B. Car driving??? C. Hands rubbing????????????? ? D.Friction discovering

4.What’s the last column(栏目)?

A. THINK IT OVER!????????????? ????????????? ????????????? ????????????? ?? B. WHAT HAPPENED?

C.EVERYDAY ACTION:????????????? D. WORK WITH PARENTS

阅读下面短文，根据其内容完成后面各项任务。
Confidence is very important in daily life. It can help you to develop a healthy attitude (态度). A study shows that the people who are more confident are much happier. They can have more chance to make themselves successful. Here are some suggestions about how to be more confident.
Speak loud   When you are not confident, you can’t do well what you want to do. You speak in a voice so low that other people can hardly hear you. Try to speak _______(1) enough so that people can hear you clearly. The high voice can _______(1) you become more confident.
Play sports   Physical exercise makes you tired but completely relaxed. A strong body helps you be full of confidence.(2)
Encourage yourself  Write down a list of things you did during the day to see how many things you have done well. Did you finish your homework? Did you tell a joke that made everybody laugh? Give yourself praise for the good things you’ve done.
Pick up a hobby   If you like singing, sing as much as you can. In some ways, a hobby can make you outstanding. And it will make you happy and confident.
Get rid of (消除) fear  Fear comes along with failure (失败). But it’s easy to overcome (克服) if you know that failure is part of your life. Don’t hide your head just because you said something stupid last time. Try to start again and believe you can do better.
【小题1】在(1)处横线上填入适当的词。___________　___________
【小题2】将（2）处划线部分翻译成中文。______________________________________________
【小题3】回答问题How many suggestions can help you to be more confident?______________
【小题4】找出并写出所给句子的同义句。
If singing is your favourite, you can sing as often as possible.__________________________
【小题5】找出并写出最能表达该短文主题的句子。
__________________________________________________________________________________________

One day Jack met his good friend Sue in the park. A dog was looking up at the woman beside her.

　  Jack walked up to Sue and said, “Hello, how are you? May I sit and talk with you for a moment?” “Of course, please sit down,” Sue said. Jack sat down next to Sue on the bench, and they talked quietly together. The dog continued to look up at Sue, as if( 似乎) waiting to be given some food.

　 “That's a nice dog, isn't he?” Jack said, pointing at the animal.

　 “Yes, he is. He's handsome. He's strong and healthy.”

“And hungry,” Jack said. “He hasn't taken his eyes off you. He thinks you've got some food for him.”

　 “That's true,” Sue said. “But I haven't.”

　　They both laughed and then Jack said, “Does your dog bite（咬）?”

　　“No, ”Sue said, “ He's never bitten anyone. He's always gentle and friendly.”

　　Hearing this, Jack decided to hold out his hand and touched the animal's head. Suddenly it jumped up and bit him.

　　“Hey!” Jack shouted. “You said your dog didn't bite.”

　　Sue answered in surprise, “Yeah, I did. But this is not my dog. My dog is at home.”

1.Jack and Sue were ________.

A．friends                               B．neighbors

C．classmates                             D．brother and sister

2.The dog looked at the woman because _______.

A．the woman wanted to feed him             B．the woman was friendly

C．he was strong and healthy                 D．he was hungry

3.Jack touched the dog because he believed _______.

A．the dog was handsome                   B．Sue's dog was unfriendly

C．the dog belonged to Sue                  D．Sue's dog was at home

4.We can guess from the story that _______.

A．Sue gave a wrong answer                 B．Jack made a mistake（错误）

C．the dog wasn’t dangerous                D．both Jack and Sue liked the dog

5.Which of the Following can be the best title of the passage?

A．A Wrong Question                      B．Sue's Dog

C．A pleasant talk                          D．Sue's Friend

One day Jack met his good friend Sue in the park.A dog was looking up at the woman beside her.
　  Jack walked up to Sue and said, “Hello, how are you? May I sit and talk with you for a moment?” “Of course, please sit down,” Sue said.Jack sat down next to Sue on the bench, and they talked quietly together.The dog continued to look up at Sue, as if( 似乎) waiting to be given some food.
　 “That's a nice dog, isn't he?” Jack said, pointing at the animal.
　 “Yes, he is.He's handsome.He's strong and healthy.”
“And hungry,” Jack said.“He hasn't taken his eyes off you.He thinks you've got some food for him.”
　 “That's true,” Sue said.“But I haven't.”
　　They both laughed and then Jack said, “Does your dog bite（咬）?”
　　“No, ”Sue said, “ He's never bitten anyone.He's always gentle and friendly.”
　　Hearing this, Jack decided to hold out his hand and touched the animal's head.Suddenly it jumped up and bit him.
　　“Hey!” Jack shouted.“You said your dog didn't bite.”
　　Sue answered in surprise, “Yeah, I did.But this is not my dog.My dog is at home.”
【小题1】Jack and Sue were ________.

Confidence is very important in daily life. It can help you to develop a healthy attitude (态度). A study shows that the people who are more confident are much happier. They can have more chance to make themselves successful. Here are some suggestions about how to be more confident.

Speak loud  When you are not confident, you can't do well what you want to do. You speak in a voice so low that other people can hardly hear you. Try to speak _______(1) enough so that people can hear you clearly. The high voice can _______(1) you become more confident.

Play sports .Physical exercise makes you tired but completely relaxed. A strong body helps you be full of confidence.(2)

Encourage yourself  Write down a list of things you did during the day to see how many things you have done well. Did you finish your homework? Did you tell a joke that made everybody laugh? Give yourself praise for the good things you've done.

Pick up a hobby.If you like singing, sing as much as you can. In some ways, a hobby can make you outstanding. And it will make you happy and confident.

Get rid of (消除) fear  Fear comes along with failure (失败). But it's easy to overcome (克服) if you know that failure is part of your life. Don't hide your head just because you said something stupid last time. Try to start again and believe you can do better.

1.在(1)处横线上填入适当的词。___________　___________

2.将（2）处划线部分翻译成中文。______________________________________________

3.回答问题How many suggestions can help you to be more confident?   

______________                                              

4.找出并写出所给句子的同义句。

If singing is your favourite, you can sing as often as possible.

5.找出并写出最能表达该短文主题的句子。