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"let"带头的祈使句
由"let"带头的祈使句(Imperative Sentences)是个常见的动词句型,它的主要用法有下列三种：
1.表示“建议”.
这个句型里的"let"后头紧跟着一个第一人称的代词宾语,如：
(1) Let me try.
(2) Let's do it.
(3) Let me go and look for it.
这个句型语气委婉,比直接的祈使句客气.试比较(4)a和(4)b:
(4) a.Don't disturb him.
b.Let's not disturb him.
(a)是直接命令,语气强烈,不如(b)温柔悦耳.
2.表示“间接命令”或“愿望”.
这句型里的动词宾语是第三人称名词或代词,如：
(5) Let Robert take charge of the marketing department.
(6) Let her join our choir.
3.表示“警告”、“蔑视”、“威胁”等.
这种祈使句里的宾语也是第三人称为主.除了口气凶悍之外,有时还语带讽刺,如：
(7) Let him try and he will expose his inability to work on his own.
(8) Let the invaders come and our armed forces will wipe them out in no time