一、用 when 或 while 完成句子。
1. Mary was reading,Lisa arrived.
2. Susan was ten, she could play the guitar.
3. I was cleaning my sister was making the bed.
4. What were you doing the accident happened?
5. Jim was walking on the street he found a watch.

1.While/When 2.When 3.while 4.when 5.when

二、用括号内所给单词的适当形式填空。
6. Betty (read) a magazine at eight yesterday evening.
7. Alice (not do) her homework when her mum came back.
8. Bill hurt himself while he (cook) dinner.
9. —I called you just now, but you didn't answer. What were you doing?
—Sorry, I (take) a shower.
10. While we (sing) an English song, some visitors came into our class.

6.was reading 7.wasn't doing 8.was cooking 9.was taking 10.were singing