一般情况下直接+ing
eg:crying jumping eating...
结尾为一个辅音一个元音一个辅音结尾的,把末尾字母双写加ing（除元音加y）
eg:running stuying buying...
两个动词连一起,第二个要改成-ing形式.
介词后面的动词要改成-ing形式
动词用作名词如动词作主语要改成-ing形式.
辅音字母+e结尾的单词要去e加ing；
有些ie结尾的单词如die,lie要把ie变成y加ing；
重音在最后一个音节的单词,要末尾双写加ing；
还有就是几个特殊的,就不说了.
一、 下列结构含有ing:
1.keep doing
2.keep /carry on doing
3.keep sb.Doing
4.enjoy doing
5.finish doing
6.be afraid of doing
7.be worth doing
8.be busy doing
9.how about doing//what about doing
10.spend some time (in)doing
11.spend some money (in) buying
12.feel like doing
13.stop/keep/prevent … from doing
14.thank you for doing
15.thanks for doing
16.do some cooking/cleaning/reading/shopping/washing
17.go swimming/fishing/shopping/skating/boating
18.mind/practise doing
19.prefer doing … to doing…
20.can’t help doing
21.there is/are +n.+ doing …
二、 下列结构用不带to的动词不定式：
1.had better (not) do sth.
2.would you please (not) do sth.
3.why not do sth.
4.why don’t you do sth.
5.Shall we do sth.
6.let do sth.
7.make sb.do sth.
三、 下列结构用带to的动词不定式：
1.It’s time to do sth.
2.It takes sb.some time to do sth.
3.tell/ask/want/encourage sb.to do sth.
4.Would you like to do sth.
5.It’s good/bad to do sth.
6.It’s good/bad for sb.to do sth.
7.be+adj.+enough to do sth.
8.sb.is ready to do sth.
9.It’s+adj.+ for sb.to do sth.
10.It’s+adj.+ of sb.to do sth.
11.would like/love /decide/want/wish/to do sth.
12.would like/love sb.to do sth.
13.Prefer to do sth.rather than do sth.
I prefer to stay at home rather than go out.
14.what/how/ when/where/whether to do sth
15.can’t wait to do
16.too … to do …
17.be afraid /ready/able/sure to do
五、下列结构用带to的动词不定式和ing形式含义不同：
1.stop to do/ doing
2.forget to do/ doing
3.remember to do/doing
4.go on to do/doing
5.like to do/doing
6.love to do/doing
7.prefer to do/doing
8.hate to do/doing
六、下列结构用带to的动词不定式和ing形式含义相同：
1.begin to do/doing
2.start to do/doing
3.learn to do/doing
七、下列结构用不带to的动词不定式和现在分词的含义不同：
用不带to的动词不定式强调动作的完成过程；用现在分词强调动作的进行状态.
1．hear sb do sth./doing
2.listen sb do sth./doing
3.look at sb do sth./doing
4.see sb do sth./doing
5.watch sb do sth./doing
6.notice sb do sth./doing
有重音,且最后1.个字母为辅音,倒数第二个为元音``
双写最后那个字母 +ing
有e结尾的去e +ing
剩下的都是直接+ing