One of the{#blank#}1{#/blank#} is my friend.
Tony is the{#blank#}2{#/blank#} boy in our class.
The students are busy{#blank#}3{#/blank#} their classroom .
The maths problem is easy, I can do it{#blank#}4{#/blank#} .
I'd like to collect {#blank#}5{#/blank#} because it's interesting.

A: Where did you go last night?

B: I went to see a robot show.

A: That sounds {#blank#}1{#/blank#}. And it means you saw real robots?

B: Yes. They looked very funny.

A: What did they {#blank#}2{#/blank#}?

B: They sang and {#blank#}3{#/blank#}, sometimes fast and sometimes slowly.

A: Could they speak like people?

B: One of them could. {#blank#}4{#/blank#}it offered customers food, it could answer their simple questions. Though its voice sounded a little strange. It could speak very {#blank#}5{#/blank#}.

A: How wonderful! I hope I can go.

Since August，driverless taxis can run on roads in cities including Wuhan，Chongqing（科技） into reality，sad China Daily.

Why do we develop self—driving cars？

Self—driving cars give us many benefits（好处）.They use computers to sense（感知） the things around them and make better use of space.This means fewer traffic jams and better parking of cars.For disabled（残疾的），self—driving cars can also help them get around more easily.By using computers，they can avoid unskilled，careless or drunk driving and so on.This can cut down 90 percent of road accidents，said the website TechDim.

Is self—driving cars totally safe on roads？

Self—driving cars can't react（反应） as fast as a human driver could if something unexpected（意料之外的） happens.Also，it is difficult for self—driving cars to see clearly.The car's computer could also get hacked（非法入侵），making it crash（碰撞），technology companies are working on these problems.

We can do many interesting chemical tests in our class. Today, we will use CO2 to blow up a balloon! Mixing baking soda(小苏打) with vinegar(醋) together can give off the CO2

What you'll need

1)A balloon       2)About 40 ml of water         3)A soft drink bottle      4)Vinegar

5)A teaspoon of baking soda Instructions

Instructions

●Before you begin, make sure that you pull the balloon long to make it as easy as possible to blow up. 

●Put the 40 ml of water into the soft drink bottle. 

●Add the baking soda and mix it with water. 

●Put the vinegar in and quickly put the balloon over the mouth of the bottle. 

What's happening?

If all goes well then the balloon should become bigger and bigger! Adding the vinegar to the baking soda creates a chemical effect. The baking soda is a base(碱), while the vinegar is an acid(酸). When the two are mixed, they'll create CO2. The gas rises up and runs away through the soft drink bottle. However, it doesn't get away from the balloon, pushing it outwards and blowing it up.