1 . — I’ll ask the teacher about the attributive clause. I’m very puzzled about it.
— That’s just __________ most of our classmates have doubt.

2 . —I drove to Zhuhai for the air show last week.
—Is that ______ you had a few days off?

A．why

B．because

C．where

D．when

4 . He didn’t finish his homework on time. That is________ he was punished by the teacher. （用适当的词填空）

5 . The problem is ________ we can get the things we need. (用适当的词填空)

6 . —I prefer shutting myself in and listening to music all day on Sundays.
—That’s ______ I don’t agree. You should have a more active life.

A．where

B．how

C．when

D．what

7 . Have you found the red mark(记号) on the map? This is ________ Huashan High School lies.

8 . A ship in harbor is safe, but that is not________ ships are built for. (用适当的词填空)

9 . Go and get your coat. It is ______ you left it.

10 . The last time we had great fun was ________ we were visiting the Water Park.