Let's go see a movie
If I can go, I can say, “Alright, OK, sounds good.”
If I can't go, I say, “I can't go, I have to...”
Right?
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Sign up to join this communityLet's go see a movie
If I can go, I can say, “Alright, OK, sounds good.”
If I can't go, I say, “I can't go, I have to...”
Right?
Let's is a contraction of Let us so, in your example sentence, the person is really saying "Let us go see a movie." It is indeed a suggestion to go and view a movie together.
Note that, although it is phrased as a command, cultural convention is to interpret it as a suggestion.
So, to answer your question, either response would be fine.
It's a simple suggestion to which you can answer with:
If you don't want to go: