The following modal verbs can be used to talk about things that are possible now or that can happen in the future:
•May / May not
👉 I may buy a book for the trip. It can be boring otherwise (puede que compre…)
👉 She may not buy a new car. It’s a lot of money! (puede que no compre…)
•Could
👉 I could get your after work, if you want
👉 Could you help me tomorrow?
•Might / Might not
👉 I might reconsider the offer (puede que…)
👉 I might not go to the party (puede que no…)
Be careful! If we use couldn’t we are saying that something didn’t happen, so it is not a possibility
👉 Lisa couldn’t go to the party → 100% sure she didn’t go the party
👉 We couldn’t finish in time → 100% sure we did not finish in time