动词不定式
问题描述：
动词不定式
She was heard ( ) an English song in her room last niant .
A sing B sang C to sing D singing
该选什么?be was heard to do
答
对,选C
在 feel,hear,listen to,look at,notice,observe,see,watch,have,let,make 等词后的补足语中,不定式不带 to.但是这些句子如果变成被动结构 时,就必须带 to.