to do 不定式
不定式的形式、意义
形式：一般式—to do；被动—to be done
完成式—to have done；被动—to have been done<br>（非谓语动作发生在谓语动词之前）
进行式—to be doing；被动—to be being done<br>（非谓语动作与谓语动词同时发生）
不定式作主语
直接作主语
To love is to give.
it作形式主语
It is + adj. + for sb. + to do sth.
It is + adj. + of sb. + to do sth.
It is + n. + to do sth.——It's an honor for me to speak here.
不定式作宾语
后直接跟不定式作宾语的动词
want, decide, determine, refuse, hope, wish, plan, learn,fail, choose, <br>expect, happen, help, manage, offer, promise, pretend, suppose
it做形式宾语—主语+think/believe/consider/feel/findtake/make/suppose+it+adj./n/+to do sth.
不定式作定语
不定式作状语
目的状语
to do / in order to / so as to（为了...），其中so as to不能用于句首
结果状语
only to do（结果却......)
only to be done（却被......）
特殊疑问词+to do不定式
作主语： Where to go is still unknown.
作宾语： I know how to find it.
doing动名词
动名词和现在分词的区别：动名词为名词性质，作主语、宾语、表语、同位语；现在分词作定语和状语
动名词作主语
直接作主语： Seeing is believing.
it 作形式主语： It is + no use/no point/no good / no fun/no help... +(in) doing sth.
后跟动名词作宾语的动词：enjoy, finish, avoid, suggest, imagine, admit…
一些动词后既可跟不定式，又可以跟动名词，意义不同：regret, remember, forget, try, stop, mean, go on…
分词
现在分词与过去分词
现在分词：一般式—doing；被动—being done
完成式—having done；被动—having been done<br>(非谓语动作发生在谓语动作之前，且对谓语有影响)
过去分词—done
分词作定语
前置定语： the falling leaves（正在落下的叶子） <br> fallen leaves（已经落下的叶子）
后置定语： The boy wearing a blue shirt is my brother.<br> The boy called Tom is my brother.
分词作状语
总的要求：分词的逻辑主语须与整个句子的主语保持一致。<br>逻辑主语与分词的关系为主动用现在分词；为被动关系用过去分词；<br>分词可作时间、原因、伴随、目的等状语
She came into the supermarket, followed by her children.
Seeing from the mountain, I can see the whole city.
Having finished her task, she can go out for a walk.
非谓语作宾补
五看”(watch, notice, observe, see, look at)、<br>“三让/让”(make, let, have)、“两听”(listen to, hear)、<br>发现find、 感觉feel
to do(省to)：表示动作发生的全过程/习惯性、经常性的动作。<br>doing：表示动作正在发生/主动关系。<br>done：表示动作已经完成/被动关系。
I heard her sing a song.(省略to)<br>被动语态：She was heard to sing a song by me.(to还原)
with引导的独立主格结构
基本结构： (with) + 名词/代词 + 非谓语
to do：动作将要发生<br>
doing：主动关系/正在进行
done：被动关系/已经完成
