You can pay now if you have some proof of identity. (AS)
You can pay now as long as you have proof of identity.
I didn't earn enough so now I'm poor. (WOULD)
If I'd earned more, I would be rich now.
How much money did you borrow from the bank? (LEND)
How much money did the bank lend you?
If you change your mind, let me know.(should)
Let me know should you change your mind.
I regret all the money spent on my new car. (wish)
I wish I hadn't spent all that money on my new car.
If they don't change their minds, we're meeting at two o´clock. (UNLESS)
We're meeting at two o'clock unless they change their minds.
Is it Ok if Molly join us too? (MIND)
Do you mind if Molly join us too?