－The classroom is so dirty, ________ we clean it?

　　－Of course.

[　　]

We will let him know that help is ________.

[　　]

If we ________ how to respont, we can save lives.

[　　]

　　－Are you still thinking about yesterday’s game?

　　－Oh, that’s ________.

[　　]

A．what makes me feel excited

B．whatever I feel excited about

C．how I feel about it

D．when I feel excited

________ there likely ________ anyone to meet us at the airport?

[　　]

Looking after the little grandson is ________ of the old couple. He brings them much ________.

[　　]

　　－Will he come to help us?

　　－Yes, I ________.

[　　]

Every possible means ________ to prevent the air pollution, but the sky is still not clear.

[　　]

They need ________ the walls of the zoo, that is, the walls of the zoo need ________.

[　　]

Yesterday they travelled ________ the foot of the mountain.

[　　]