1.stop to do sth. 和stop doing sth.

　　“stop to do sth.” 表示停止做其它事情而去做“to do sth.”所表示的事情，可以將“to do sth.”理解成“stop”的目的狀語：“stop doing sth.”表示不做“doing sth.”所表示的事情。

　　例如：“Stop talking. Let's begin our class.”said the teacher. 老師說：“別說話了，讓我們開始上課。”

　　We have kept doing our homework for a long time. Let's stop to listen to music. 我們做家庭作業很長時間了，讓我們停下來聽聽音樂。

　　2.have sth. done.(過去分詞)(讓別人)做某事

　　例如：I had my hair cut yesterday afternoon. 我昨天下午理了發。

　　My computer can not work now. I must have it repaired. 我的電腦有故障了，我必須讓人修好它。

　　3.forget to do sth.和forget doing sth. (remember to do sth. 和remember doing sth.)

　　“forget to do sth.”表示將來不要忘記做某事，談的是未來的事情：“forget doing sth.”表示忘記過去應該做的事情。

　　例如：“Don't forget to do your homework.”said the teacher before the class was over.

　　老師在下課前說：“不要忘記做家庭作業。”

　　“I'm sorry. I forgot doing my homework. May I hand it in this afternoon，Mr. Chen?”said Li Ming.

　　李明說：“對不起，我忘記做家庭作業了。我今天下午交好嗎，陳老師?”

　　4. 感官動詞后接不帶to的不定式或者現在分詞的區別

　　例如：see sb. do sth.看見某人(經常)做某事 和see sb. doing sth.看見某人(正在)做某事

　　I often see him do exercise in the morning. 我經常在早晨看見他鍛煉身體。

　　When I was walking in the park，I saw him drawing a picture there. 當我在公園散步的時候，我看見他正在那里畫畫。

　　5. 介詞后面一般接動名詞。同學們要特別注意介詞to和不定式符號to的區別，例如下面的詞組一定要記清：

　　prefer doing sth. to doing sth. 喜歡做……不喜歡做……

　　look forward to doing sth. 期待/盼望做某事

　　make a contribution to doing sth. 為……做出貢獻

　　6. 在主動語態中，感官動詞(see，hear，feel，watch等)和使役動詞(make，have，let等)要求接不帶to的不定式做賓語補足語，而在被動語態里，不定式要帶上to.

　　例如：The boss often made the workers work 10 hours a day.

　　The workers were made to work 10 hours a day.