1--Gravity is very important.

2--What is gravity?

1--It's the force that pulls everything down.

2--I don't understand.

1--If you pour water into a glass, the water goes down into the glass.

2--Of course it does.

1--Without gravity, the water would go up.

2--You're joking.

1--Without gravity, you would go up.

2--What do you mean?

1--You would float into the sky like a balloon.

2--That would be fun!

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注解：

1.Gravity重力

2.Of course当然    

3.go up上升  

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译文：

1--重力非常重要。

2--什么是重力？

1--它是使万物下降的力。

2--我不理解。

1--如果你向杯子里倒水，水会流向杯子的下方。

2--它当然会那样。

1--没有重力，水就会上升。

2--你在开玩笑。

1--没有重力，你会上升。

2--你的意思是？

1--你会像气球一样漂浮在空中。

2--那将会很有趣！