4.不定式作have、make、let、feel、see、watch、 notice、hear、listen to、look at等动词（短语） 的宾语补足语时不带o,作主语补足语时（即被动语 态之后)则要带to。 Her parents wouldn't let her go out alone. I heard him say that he was tired. 试比较：He made me move my car.(作宾语补 足语) I was made to move my car.(作主语补足语)
4.不定式作have、make、let、feel、see、watch、 notice、 hear、listen to、look at等动词（短语） 的宾语补足语时不带to，作主语补足语时（即被动语 态之后）则要带to。 Her parents wouldn't let her go out alone. I heard him say that he was tired. 试比较：He made me move my car.（作宾语补 足语） I was made to move my car.（作主语补足语）
不定式符号的省略 l.在使役动词have,let,make之后。 2.在感官动词feel,hear,see,watch,notice, observe,listen to,look at之后。 3.在why和why not之后。 4.在其他结构之中。如： a.can do nothing everything but except do b.cannot help/choose but do c.cannot but do d.had better do sth e.would rather do sth f.help sb (to)do sth help (to)do
不定式符号的省略 1.在使役动词have， let， make 之后。 2.在感官动词 feel， hear， see， watch， notice， observe， listen to， look at 之后。 3.在 why 和 why not 之后。 4. 在其他结构之中。如： a.can do nothing / everything but / except do b. cannot help / choose but do c. cannot but do d. had better do sth e. would rather do sth f. help sb (to) do sth 或 help (to) do