A lets
1 lets通常表示建议，在间接引语中用动词suggest转述：
He said，Lets leave the case at the station.
他说：我们把箱子存在车站吧!
可转述为：
He suggested leaving the case at the station./He suggested that they/we should leave the case at the station.
他建议他们/我们把箱子存在车站。
He said，Lets stop now and finish it later.
他说：现在停下来，以后再完成它。
可转述为：
He suggested stopping then and finishing it later./He suggested that they/we should stop then and finish it later.
他当时建议(他们/我们)那时先停下来，以后再来完成。
否定式也是这样：
He said，Lets not say anything about it till we hear the facts.
他说：在我们没有听到事情的真相之前，对这件事什么话也别说。相当于：
He suggested not saying anything/saying nothing about it till they heard the facts./He suggested that they shouldnt say anything till they heard the facts.
他建议他们在没有听到事实真相之前什么都别说。
但如果单独使用lets not对一个肯定的建议做出答复，那么在转述时常用下列短语：opposed the idea/was against it/ob-jected。因此：
Lets sell the house，said Tom.
汤姆说：我们把这房子卖了吧。
Lets not，said Ann.
安说：我们别卖。
可转述为：
Tom suggested selling the house but Ann was against it.
汤姆建议把房子卖了，但是安表示反对。
2 lets/let us有时表示对一种行动的号召，这时通常由urge/ad- vise+宾语+不定式结构表示
The strike leader said，Lets show the bosses that we are united.
罢工领导人说：我们给老板看看我们是团结一致的。相当于：
The strike leader urged the workers to show the bosses that they were united.
罢工领导人鼓动工人们给老板们看看他们是团结一致的。
B let him/them
1从理论上讲let him/them表示命令。但实际上说话人对受命人时常并没有发号施令的权威：
Its not my business，said the postman.Let the government do some- thing about it.
这事与我无关。邮递员说，叫政府去想办法吧。
这里说话人并不是在发号施令，而只是表示责任在谁身上，因此这类句子通常由ought/should来转述：
He said that it wasnt his business and that the government ought to/ should do something about it.
他说这不关他的事，而是政府应该对这事想点办法。
2但有时let him/them表示真正的命令，在转述时常用say+be+不定式结构：
Let the boys clear up this mess，said the headmaster.
校长说：这些脏乱的东西该由男孩子们去收拾。相当于：
The headmaster said that the boys were to clear up the mess.
校长说那些脏乱的东西让男孩子们去收拾。
Let the guards be armed，he ordered.
他命令道：警卫人员要佩带武器。相当于：
He odered that the guards should be armed.
他命令说警卫人员必须佩带武器。
3 有时let him/them更多地表示建议而不是表示命令。在这种情况下，常用suggest或say+should来转述
She said， Let them go to their consul.Hell be able to help them.
她说：让他们去找他们的领事，他会帮助他们的。相当于：
She suggested their/them going to their consul.../She suggested that they should go to their consul/She said that they should go to their con- sul...
她建议他们去找他们的领事
4 let him/them也可以表示说话人对某事不在乎：
The neighbours will complain，said Ann.
安说：邻居会抱怨的。
Let them(complain)，said Tom.
汤姆说：让他们(抱怨)去吧。相当于：
Tom expressed indifference.
汤姆满不在乎。
Tom said he didnt mind(if they complained).
汤姆说(要是他们抱怨)那他也不在乎。
C let there be
说话人这样说时可以表示命令、劝告、催促或请求：
Let there be no reprisals，said the widow of the murdered man.
害者的遗孀说：千万不要搞复仇。相当于：
The widow urged/begged that there should be no reprisals.
遗孀敦促/祈求不要去搞复仇。
D let也是一个普通动词，意为allow/permit(允许)：
Let him come with us，mother;Ill take care of him，I said.
我说：妈妈，让他跟我们一起去吧，我会照顾他的。相当于：
I asked my mother to let him come with us and promised to take care of him.
我请求妈妈让他和我们一起去，并保证我会照顾他的。