Page 335 - Practical English Usage 3ed - Michael Swan, Oxford

I'll let you know my holiday dates next week.
Could you let me have the bill for the car repair? Let go o f means 'stop holding'.
Don't let go ofMummy's hand.
2 not used in passives
Let is unusual in passive forms; we prefer allow. After questioning he was aUowed to go home.
3 with object + preposition I adverb particle
Let can be followed by an object and a prepositional phrase or adverb particle expressing movement.
You'd better let the dog out ofthe car.
Let him in, could YOlt? Those kids let my tyres down.
For more about infinitives without to, see 281.
323 let (2): introducing imperatives
Let can be used to introduce suggestions and orders, when these are not addressed to the hearer/reader (or not only to the hearer/reader). This structure can be considered a kind of imperative (see 268).
1 first-person plural imperative: let's . ..
We can use let us (formal) or let's (informal) to make suggestions or to give orders to a group that includes the speaker.
Let us pray. Let's have a drink. OK. let's all get moving.
Shall we? is used as a question tag (see 487-488) in British English; let's can be used as a short answer.
Let's go for a walk, shall we? - Yes, let's.
Negatives are let us not / do not let us (formal); let's 1Iot I don't let's (informal).
Let us not despair. (formal) Let's not get angry. (informal) Do not let us forget those who came before us. (formal) Don't let's stay up too late tonight. (informal)
2 first-person singular imperative: let me ...
Let me is used to 'give instructions to oneself; the expressions Let me see and Let me think are very common.
What time shall we leave? - Let me think. Yes, Eight o'clock will be OK What's the best way to Manchester? Let me see - suppose I take the M6. Let me just get my coat and I'll be with you.
In a very informal style, let's is often used to mean let me (see also 429.6). Let's see. Suppose I take the M6 ...
3 third-person imperative: let him . ..
Let can also introduce a suggestion or order for someone or something else, not the speaker or hearer. This is common in formal and ceremonial language,
but informal uses are also possible.
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let (2): introducing imperatives 323
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