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，可以将to do sth。理解成sTOP的目的状语;sTOP doing sth。表示不做doing sth。所表示的事情。
比如： STOP talking. Lets begin our class。 said the teacher. 老师说：不要说话了，让大家开始上课。
We have kept doing our homework for a long time. Lets sTOP to listen to music. 大家做家庭作业很久了，让大家停下来听听音乐。
2.forget to do sth。和forget doing sth.
forget to do sth。表示以后不要忘记做某事，谈的是将来的事情;forget doing sth。表示忘记过去应该做的事情。
比如： Dont forget to do your homework。 said the teacher before the class was over.
老师在下课前说：不要忘记做家庭作业。
Im sorry. I forgot doing my homework. May I hand it in this afternoon, Mr. Chen? said Li Ming.
李明说：对不起，我忘记做家庭作业了。我今天下午交怎么样，陈老师?
3.have sth. done。做某事
比如：I had my hair cut yesterday afternoon. 我昨天下午理了发。
My computer can not work now. I must have it repaired. 我的电脑有问题了，我需要叫人修好它。
4. 感官动词后接不带to的不定式或者目前分词有什么区别
比如：see sb. do sth。看见某人做某事 和see sb. doing sth。看见某人做某事
I often see him do exercise in the morning. 我常常在早晨看见他训练身体。
When I was walking in the park, I saw him drawing a picture there. 当我在公园散步的时候，我看见他正在那里画画。
5. 在主动语态中，感官动词和使役动词需要接不带to的不定式做宾语补足语，而在被动语态里，不定式要带上to。
比如：The boss often made the workers work 10 hours a day.
The workers were made to work 10 hours a day.
She was heard to use strong language. 听说她骂人了。
6.常见的几个和不定式有关的句型：
Why not do sth? 为何不做某事?
It takes/took sb. some time to do sth. 做某事花了某人多久。
It is/was +形容词+ +to do sth. 做某事如何。
7. 介词后面一般接动名词。同学们要特别注意介词to和不定式符号to有什么区别，比如下面的词组必须要记清：
prefer doing sth. to doing sth. 喜欢做不喜欢做
look forward to doing sth. 期待/盼望做某事
make a contribution to doing sth. 为做出贡献
8. 目前分词和过去分词做定语有什么区别
A. 目前分词含有正在进行的意思，而过去分词含有被动或者已经完成的意思，如：
a developing country 进步中国家 a developed country 发达国家
boiling water 正在沸腾的水 boiled water 开水
a boy named Jim 一个叫Jim的男生
B. 有的动词的目前分词和过去分词都具备形容词特点，但它们的意思有不同。它们的-ing形式总是用来讲明事物的特点;他们的-ed形式表示被动的意思，用来讲明人的状况。
I am interested in this interesting story. 我对这个有趣的故事有兴趣。
I am moved at the moving sight. 我被这动人的情景感动了。
They were amazed at the amazing facts. 他们对那些让人惊异的事实感到惊奇。
