I'll get a work premit. I'll stay for another month
-->If I get a work permit, I'll stay for another month
He doesn't take any exercise. He is so unhealthy
--> If he took any exercise, he would be healthy
We can't get the ticket because I don't have a right change
-->If I had the right change, we could get the ticket
Study hard or you won't pass the exam
--> Unless you study hard, you won't pass the exam
Don't be impatient or you will make mistakes
-->If you be impatient, you will make mistakes

I didn't eat lunch, I feel hungry now
--> If I had eatten lunch, I would't have felt hungry
If they don't invite me, I won't come
-->Unless they invite me, I won't come
He didn't revise all his lesson, he failed the axam
-->If he had revised all his lesson, he woudn't have failed the exam
Leave me alone or I'll call thepolice
-->If you don't leave me alone, I'll call the police