写出句子所缺的词的适当形式。
（1）The pupils ______ (watch) the play yesterday evening.
（2）Mike ______ (do) some _______ (read) in the library every Monday.
（3）The boy ________ (help) his sister _______ (make) the snowman now.
（4）The children _______ (plant) the trees on the hill this morning.
（5）The woman ________ (go) to the market last Sunday.
（6）I _______ (have) a cold last week.