Making a suggestion:
How about+gerund (v+ing)...?
That's a good/great idea!
Yes, let's.
Yes, I'd like/love to.
That sounds like a good idea.
That sounds like a good idea.
Yes, I feel like + gerund ...
Declining/Refusing/Rejecting/Turning down:
What about+gerund (v+ing)...?
Why not+infinitive...?
Let's (not)+infinitive
What would you say to...?
Don't you think it is a good idea to...?
Does it matter if we...?
Shall we...?
Accepting:
Why not?
That's a good/great idea!
Yes, let's.
Yes, I'd like/love to.
That sounds like a good idea.
That sounds like a good idea.
Yes, I feel like + gerund ...
Declining/Refusing/Rejecting/Turning down:
No, let's not.
No, I'd rather not.
I dislike+ gerund...
I dislike+ gerund...
What an awful/bad idea!
Yes, but...
Dialogue:
Two friends talking about where to go this evening:
Alice: You know Alan, why don't we go to the cinema to watch Titanic? Alan: No, let's not. We've seen the film many times before. What about going to the library? We have to finish our school project! Alice: That sounds like a good idea. But when we finish let's go to the cafè. Alan: Yes, I'd love to.