【注意】 1) 主动语态变为被动语态要加“to”的情况 以下动词变为被动语态时,要在其后加“to”。 此类动词为感官动词,如:feel, hear, help, listen to, look at, make, observe, see, notice, watch等。 例如: The teacher made me go out of the classroom. I was made to go out of the classroom (by the teacher). They made him cry. (主动语态) He was made to cry by them. (被动语态)
2) 主动形式表示被动意义 如wash, clean, cut, read, wear, draw, write, sell等动词虽然用做主动形式却表示被动的意义。例如: The pen writes smoothly. This kind of cloth washes easily. 感官动词如feel,look,smell,taste,sound等直接跟形容词作表语。 The food tastes good.
3)want, need, require表示“需要”时,后接-ing表被动; ①Sth. want/need/require to be done=sth. want/need/require doing Your hair needs cutting= Your hair need to be cut.你的头发需要被剪 ②be worth+doing sth.值得被做...。The book is worth reading.