Conditionals with modal verbs and imperatives · We can use modal verbs ( should, can, etc. ) in the main clause of conditionals: If parents want their kids to grow up healthy, they shouldn't protect them so much. But if kids never go outside, they can't learn to look after themselves. · We can also use imperatives ( give, don't tell, etc.) in the main clause of conditionals: If you want happy and healthy kids, give them back their freedom. If you come home late, don't wake me up. · In these conditionals we use the Present Simple in the if clause: If you need some help, call me. *We can use other modal verbs ( must, have to, might, etc.) in these types of conditionals: If you don't understand the instructions, you must tell me immediately.