1 . The true value of life is not               but what you have done. (gain)
生命的真正价值不在于你得到什么，而在于你做过什么。

2 . 那就是我们总是努力吃得健康并且经常锻炼的原因。
______________________________ we always try to eat in a healthy way and exercise regularly．

3 . He overslept this morning. That’s _______ he was late for the class.

4 . Jim fell asleep in the math class today. That is ___________ he stayed up until midnight doing his homework.

5 . Whether ways will be found to stop pollution or not is just _____ worries the public. （用适当的单词填空）

6 . What has caused great confusion is ____________ the scientist made it without anyone else’s help. (用适当的词填空)

7 . Education is ______________ survives when knowledge taught in class has been forgotten.

A．how

B．who

C．what

D．which

8 . Social media paints this rosy picture that everyone else 's lives are perfect,but things are seldom_______they seem.

A．which

B．what

C．how

D．where

9 . As days go on，I think that Beijing will become ________ the whole world pay close attention to.

A．where

B．what

C．which

D．that

10 . It is years since he worked here, but his devotion to his work is________we often hear Spoken of.

A．what

B．that

C．when

D．why