使役动词顾名思义就是使人……奴役……，让……做某事的意思。
最常用的有：Let ，have，make
这几个动词跟不定式搭配，符号to省略，用let/have/make sb. do sth.
The teacher let the students clean the classroom .
不完全及物动词
使役动词是表示使、令、让、帮、叫等意义的不完全及物动词,主要有leave（离开）.get（得到）.make(使,令),let(让),have(有；让；从事；允许；拿)等。
使役动词后接宾语,再接省略to的动词不定式作宾语补足语。
接宾语时，人称代词用宾格。
例句
1.使役动词可接动词原形作宾语补语。
1）He makes me(宾格) laugh.
他使我发笑。
2）I let him go.
我让他走开。
3）I helped him repair the car.
我帮他修理汽车。
4）Please have him come here.
请叫他到这里来。
2.使役动词还可以接过去分词作宾语补足语。
I have my hair cut every month.
我每个月理发。
3.使役动词的被动语态的受词补语用不定词,不用原形不定词。
1）(主)He made me laugh.
他使我笑了。
2）(被)I was made to laugh by him.
我被他逗笑了。
使役动词have, let, make （常用于复合结构）
1. have的用法
1）have +宾语+do（省略to的不定式）：表示主语“要”“使”“让”宾语干某事，宾语和宾补之间是一种主动关系。
The rich lady had the singer eat with her servants.这位富有的女士让这位歌手和她的仆人一起吃饭。
I will have him come and help you.我会让他来帮助你的。
2）have+宾语+现在分词：表示让某人或物连续进行某动作或处于某状态中，宾语和宾补是一种主动关系。
The two cheats had the lights burning all night long.这两个骗子让灯整晚亮着。
He had us waiting for him three hours yesterday.昨天他让我们一直等了他三个小时。
I have them all talking to each other in English.我鼓励他们用英语交谈。
3）have +宾语+过去分词：表示主语的主观意志，即主语让别人为自己完成某事，宾语和宾补是动宾关系，还可以表示主语遭受到来利或不测的事。
Tom said he had had his TV set repaired.汤姆修了他的电视机。（别人修的）
Tom had his wallet stolen on the bus yesterday.昨天汤姆使他的钱包被偷了。（别人偷的）
4）have+宾语+形容词/副词/介词短语作宾补，Please have your tickets ready.请准备好你的票。
The Emperor had nothing on.这位皇帝什么都没在做。
I am sure I’ll have him in the argument.
2. let的用法
1）let +宾语+do（省to不定式）：表示主语“要”“使”“让”宾语干某事，宾语和宾补之间是一种主动关系。
Let them stay in the classroom and do their exercises themselves.让他们自己待在教室里做练习吧。
Let AB be equal to CD.假设AB等于CD.
2）let+宾语+副词/介词短语作宾补，Let me in and let them out.让我进来，让他们出去。
Who let you into the building?谁让你进到大楼里来的？
3. make的用法
1）make +宾语+do（省to不定式）：表示主语“要”“使”“让”宾语干某事，宾语和宾补之间是一种主动关系。此结构常用被动结构。
The teacher made the naughty boy stand there for an hour.老师让这个调皮的男孩在那里站了一个小时。
The naughty boy was made to stand there for an hour.这个调皮的男孩被让在那站了一个小时。
2）make+宾语+过去分词，此结构中的宾语指人时常用到反身代词。
He raised his voice to make himself heard.他提高嗓音让自己被听到。
They will make an important plan known to the public soon.他们不久就会让公众知道这个计划。
3）make+宾语+形容词，宾语亦可是从句。
The news made her happy.这个消息使她快乐。
He made it clear that he objected to the proposal.他明确表明他反对这个建议
