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。
例如：“ Stop talking. Let’s begin our class。” said the teacher. 老师说：“别说话了，让我们开始上课。”
We have kept doing our homework for a long time. Let’s stop to listen to music. 我们做家庭作业很长时间了，让我们停下来听听音乐。
2. forget to do sth。和 forget doing sth. ( remember to do sth. 和 remember doing sth。)
“ forget to do sth。”表示将来不要忘记做某事，谈的是未来的事情;“ forget doing sth。”表示忘记过去应该做的事情。
例如：“ Don’ t 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。”
“ I’m 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。我今天下午交好吗，陈老师”
3. have sth. done。(过去分词)(让别人)做某事
例如： 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. 我的电脑有故障了，我必须让人修好它。
4. 感官动词后接不带 to的不定式或者现在分词的区别
例如： see sb. do sth。看见某人(经常)做某事和 see sb. doing sth。看见某人(正在)做某事
I often see him do exercise in the morning. 我经常在早晨看见他锻炼身体。
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例如： 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.常用的几个和不定式有关的句型：
Why not do sth? 为什么不做某事
It takes/ took sb. some time to do sth. 做某事花了某人多长时间。
It is/ was+形容词+( for sb。)+ to do sth. 做某事(对某人来说)怎么样。
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的区别，例如下面的词组一定要记清
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. 现在分词和过去分词做定语的区别
A. 现在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发展中国家 a developed country发达国家
boiling water正在沸腾的水(一般情况下水温为 100℃) boiled water开水(已经烧开的水，水温可以依然很高，也可以是凉白开)
a boy named Jim一个叫 Jim的男孩
B. 有些动词的现在分词和过去分词都具有形容词特征，但是它们的意思有区别。它们的 - ing形式往往用来说明事物的特征;他们的 - ed形式表示被动的意思，用来说明人的情况。
I am interested in this interesting story. 我对这个有趣的故事感兴趣。
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. 他们对那些令人惊异的事实感到惊奇。
