奧數(shù)網(wǎng)：小編為大家準(zhǔn)備了新概念英語第一冊語法分析，一起來看看吧~

　　過去進(jìn)行時

　　——表示過去正在進(jìn)行的動作，經(jīng)常用在when, while, as引導(dǎo)的狀語從句中。

　　結(jié)構(gòu)：was/were+doing

　　When my husband was going into the dining room this morning, he dropped some coins on the floor.

　　Their father was watching TV while?they were having dinner.

　　★變疑問句將be動詞移到句首

　　Was their father watching TV while?they were having dinner.

　　★變否定句在be動詞后面加 not

　　Their father was not?watching TV while?they were having dinner.