The examples with 'let's' don't make sense. Let's is the imperative form of the offer 'Shall we?' So you would have to use this as the tag. Let's go, shall we. All the others are fine as the tag could be used to form the normal question. We don't know what the original question would have been so any of the possible tags work. Do sit down, won't you? = Won't you sit down? (do is just emphatic) Give me an apple, will you? = Will you give me an apple? Give me an apple, won't you? = Won't you give me an apple? Give me an apple, would you? = Would you give me an apple? The differences between the modal verbs are the same as in the usual situations - 'would' is less direct than 'will', etc.

In tag questions with "Let's," the tag typically uses "shall we?" rather than variations like "will you?" or "would you?" These other forms may not sound entirely natural or idiomatic, though a few are technically possible in informal contexts. Here’s an analysis: 1. Let’s go, will you? - This is somewhat unusual. It sounds slightly brusque, as if urging someone in a way that could imply impatience. It’s not common but might be used for emphasis. 2. Let’s go, won’t you? - This is not standard. "Won’t you" is more of a request or invitation in English, so it doesn’t pair naturally with "Let’s." It would usually be, "Come along, won’t you?" rather than "Let’s go, won’t you?" 3. Let’s go, would you? - This is also unusual and not idiomatic in standard English. It could come across as a bit sarcastic or impatient, depending on the tone. 4. Let’s go, can you? - This sounds awkward in English, as "can you" implies an ability rather than an encouragement to join. 5. Let’s go, can’t you? - Also uncommon and not standard. It sounds somewhat confrontational, as if the speaker is frustrated that the person isn’t ready to go yet. 6. Let’s go, could you? - Similarly to the others, this is not idiomatic. "Could you" implies asking for permission or ability, which doesn’t fit well with "Let’s go." Correct and Most Natural Tag The standard, correct form is: - "Let’s go, shall we?" Summary of Meaning Differences The variations in tone among these tags often add a sense of impatience, frustration, or even sarcasm, which is not typical for polite or neutral tag questions. "Shall we" is the only tag that sounds natural and neutral with "Let's go." The other forms may be used in informal or specific situations, but they aren’t grammatically standard. PS always use "may" rather than "can"