Thank you for your reply sir.

I have learnt some words can use present tense to express the future.

Like:

Even if it rains, I will go outside. can I change this one to: Even if you have jobs to do tomorrow, you are still playing!!!

If you booked a ticket, you can enjoy our best service now. can I change this one to: Even if you booked a ticket, you still can't enjoy the service for some reason. (here the past tense is about guessing, not the unreality)

And about Even if he had jobs to do tomorrow, he was still playing.Obviously, he was fired. (just change the first example to the past, now someone is talking about the reason why he got fired)

Thanks so much, dear teachers!