【题目】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:

●A piece of soap ●Water ●Your hands

WHAT TO DO:

1.Make sure your hands are dry.

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

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

4.Try to make friction happen while your hands are slippery.

5.Please write down what has happened.

LET'S TALK!

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

DID YOU KNOW?

1.Friction happens when you stop your fast running bike.

2.Ancient people made fires 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 too hot, touch the tires (轮胎) of the car before and after a short drive to see how much warmer they get from friction.

1You'd better make your hands ________ to get heat when you rub them.

A. slippery B. dry C. wet D. smooth

2What does the underlined 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

4What's the last column (栏目)?

A. THINK IT OVER!

B. WHAT HAPPENED?

C. EVERYDAY ACTION:

D. WORK WITH PARENTS!

5This text is most probably ________.

A. a science report B. a car advertisement

C. a rubbing introduction D. a chemistry programme

【题目】Dear Dr Bamford,

I know you are a famous scientist who has done great work on cloning animals. Please excuse me for writing to you,but I need your __________. Let me explain. I am a 58yearold man. I'm very rich. I live in a large house. My wife died three years ago; we didn't have children. So,am I _________?No,because Cindy is with me. Every night we eat dinner together and watch TV.

Cindy sits beside me __________ I feel very happy. I'm fascinated by her beautiful green eyes. She's also very smart. Sometimes she thinks only about herself. But that's what I __________ about her. She is quite a beautiful Siamese cat. There is no other cat like her in the whole world.

These days I worry about _________ Cindy. She is getting older and older. Cats don't live _________ humans,of course,so she will die before I do. I cannot imagine my life _________ Cindy.

Well,why not get another cat after Cindy dies? __________! No other cat can ever replace(替代) her. I have been thinking about cloning Cindy. Scientists are able to clone sheep, mice and other animals. You should be able to clone cats without much __________. Luckily,I am a rich man. I don't care how much I will spend cloning Cindy. I think __________ to clone pets. It's not cloning humans.

What do you think of it? Could you clone Cindy?

1A. cat B. animals C. help D. money

2A. lucky B. lonely C. healthy D. happy

3A. but B. or C. / D. and

4A. like B. hate C. mind D. stand

5A. feeding B. catching C. losing D. training

6A. as hard as B. as soon as C. as often as D. so long as

7A. with B. without C. of D. about

8A. Certainly B. Impossible C. Really D. Wonderful

9A. difficulty B. advice C. hope D. chance

10A. it's terrible B. you aren't supposed C. it's OK D. you aren't allowed

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