It is+adj./n.+(for/of sb.)+to do sth. (对于某人来说）/（某人）做某事是...
for sb. difficult escsy important impossible necessary danserous
of sb. kind nind wise caleful clever honest impolite
It taks(sb.）+时间+to do sth.做某事花费（某人)...时间
doing作真正主语
It is/was no/not any/of little good+doing sth. 做某事没有用途
It is/was useless/of little use+doing sth. 做某事没有用途
It is/was a waste of time+doing sth. 做某事浪费时间
to do/doing作宾语的用法
动词和词组用to do作宾语。（不定式否定not to do)
decide fail未能 determine决定 learn want expect hope wish refuse拒绝 manage成功 pretend假装 agree strive努力 would like想要 would love很想 would prefer更喜欢
注意：what who when where how wether+to do,但way+do
动词后用doing作宾语
consider suggest advise postpone推迟 look for ward to ; admit承认 delay推迟 forbid禁止 prohibit禁止 avoid miss keep practise deny finish enjoy appreciate can't help can't imagine ; mind allow permit允许 escape discass risk prevent
动词词组用doing作宾语
be use to习惯；lead to导致；devots to奉献；stick to ; get doen to ; pay attention to ; can't stand无法忍受；give up放弃；feel like想要；insist on坚持；keep on ; put off ; thank you for ; apologize for道歉；be busy(in）；have difficulty/trouble（in）做什么很难；have good、wonderful/hard time(in)愉快/很难做某事
注意：your his her their+doing(动名词）=名词
即可接to do也可接doing作宾语
forget todo sth.忘记去做某事 forget doing sth.忘记已经做过某事
remember todo sth.记得未做某事 remeber doing sth.记得做过某事
stop todo sth.停下来去做另一件事 stop doing sth.停止做一件事
go on todo sth.(做完某事）接着做另一件事 go on doing sth.继续做同一件事（=go on with sth.）
try todo sth.努力做某事 try doing sth.尝试着做某事
mean todo sth.打算做某事 mean doing sth.意味着做某事
can't help todo sth.不能帮助做某事 can't help doing sth.情不自禁做某事
注意：allow/advise/forbid/permit doing sth.(doing 作宾语） allow/advise/forbid/permit sb todo sth.(todo 作宾补）
sth+need/require/want+doing/to be done；need/require/want sb. todo sth.
worth worthy worthwhile的用法
worth
be+worth+sth.价值...；值得...
be+worth+doing sth.值得（被）...
worthy
be+worthy+of+sth/doing sth. ...是值得的
be+worthy+to be done.某事值得（被）...
worthwhile
It+be worthwhile to do sth....是值得的
to do在介词but； other than(除了）有实义动词do,不用带to,无实义动词do,带to
can't; choose; bu; can't help but; can't but+do
doing/done做表语的用法
-ing 形容物，“令人...的” -ed形容人，“感到...的”
doing/to do/done作宾语补足语的用法
感官动词see watch notice observe hear等和使役动词have make let后面的宾补有三种形式，即do(不带to 的不定式）、doing和done。do表示主动且完成，doing表示主动且进行，done表示被动且完成。
get sb.to do stuff.使/让/叫某人去做某事
非谓语作宾补：（…sb/sty+非谓语：逻辑主语）
get sth.done使/让某事/物被做（被动）
keep an./sth.doing 使/让某人/事/物持续做
keep sb/sth.done 使/让某人/事/物被做
如果宾补是不带to的不定式，变为被动形式时，不定式必须带to
Leave 后接三种形式作宾补时，leave应翻译为“使…处于某种状态”
leave sb./sth.doing sth. 让某人/某物一直…（主动 进行）
leave sth.undone 留下某事未被做（被动 完成）
leave sb.to do sth.留下某人做某事
leave sth.to be done 留下某事要被做（不定式表示将来的动作）
advise allow ask beg cause encourage expect force get intend forbid permit invite like love order persuade require teach tell want wish think ; wait for ; call on. ; depend on ; +sb/sth +to do作宾语补足语
to do/doing/done作定语的用法
to do作名词的后置定语
to do表示主动和将来；to be done表示被动和将来
用来修饰被序数词、最高级或no,all,any等限定的中心词
一些抽象名词通常在其后用to do作定语，如ability chance promise reply attempt way reason time.. idea fact excuse借口 answer belief moment时刻 等
