［误］ This work is difficult to be done.

　　［正］ This work is difficult to do.

　　 ［析］ 在不定式作宾语时，下列情况常用主动语态表示被动。① 句子的主语即是不定式动作的执行者，如：I have a lot of letters to write. ② 句中的宾语是不定式中动作的执行者，如：Could you find me a job to do? ③ 在形容词之后的不定式，如：English is difficult to learn.

　　 ［误］ Would you like to see a film with us?? Yes, I'd love.

　　 ［正］ Would you like to see a film with us?? Yes, I'd love to.

　　 ［析］ 在口语简答语中要将不定式符号保留，如：? I had to (不得不作) I'm going to (打算作) I used to (过去习惯作)? I'd love to (喜欢作) I hope to (希望作某事) I'll be glad to (高兴作)

　　［误］ Did you see someone to do this work for me?

　　 ［正］ Did you see someone do this work for me?

　　 ［析］ 在感观动词之后常接不带to的不定式。这些词是see, look at, watch, hear, listen to, feel, notice。

　　［误］ He was seen prepare this car.

　　 ［正］ He was seen to prepare this car.

　　 ［析］ 在被动语态中要将主动语态句中省去的不定式还原回来。

　　 ［误］ Please? Let my child to try it again.

　　 ［正］ Please? Let my child try it again.

　　 ［析］ 在make, have, let后加不带to的不定式作宾语补足语。

　　 ［误］ Why not to do it again?

　　 ［正］ Why not do it again?

　　［析］ Why not, you'd better 后接不带to的不定式，如：You'd better go.但要注意的是它的否定式是You'd better not go.

　　 ［误］ When he heard the news he couldn't help to cry.

　　［正］ When he heard the news he couldn't help crying.

　　 ［析］ can't help+现在分词表示情不自禁作某事。

　　 ［误］ In autumn, the street is always covered with falling leaves.

　　 ［正］ In autumn, the street is always covered with fallen leaves.

　　 ［析］ 现在分词作定语有正在的含义，如：falling leave 正下落的叶子。而过去分词作定语fallen leaves是落地的叶子。过去分词含有已经完成的意思。

　　［误］ Do you hear someone sing in the office?

　　 ［正］ Do you hear someone singing in the office?

　　 ［析］ 感观动词可用不带to的不定式来作宾语补足语，表达一个动作的全过程或已结束的动作，而用现在分词表示一个正在进行中的动作。

　　 ［误］ I want to shop some food for supper.

　　 ［正］ I want to buy some food for supper.

　　 ［正］ I want to go shopping.