1 . ______ is generally agreed that no one can learn all the knowledge all his life.

A．What

B．As

C．Which

D．It

3 . To help people out of trouble is his lifelong mission.(用it做形式主语改写)
_______________

4 . ________ is a pity ________ you didn’t attend the lecture last night. It was wonderful.

A．What; that

B．It; that

C．What; why

D．It; why

5 . _____ doesn’t really matter whether you win or lose. As long as you have tried your best, you won’t regret.

A．What

B．This

C．That

D．It

6 . Though he never disguised his leadership ambitions, he continued to deny that ________ to challenge the Prime Minister.

A．he had no intention

B．he had every intention

C．it was not his intention

D．it was his intention

7 . _________was a desperate race against time to land the plane before it ran out of fuel. Fortunately, the young pilot made it eventually.

A．It

B．This

C．What

D．As

8 . ______ remains doubtful ______ this is an important discovery.

A．That; whether

B．That; that

C．It; whether

D．It; that

9 . ________ never occurred to me ________ I had to attend an important meeting in Shanghai the next day.

A．lt; which	B．What; that
C．What; which	D．It; that

10 . In the past, ____didn’t make much of a difference to your success____ you had a good family background.

A．that; if

B．it; whether

C．that; whether

D．it; if