1/ We won't go out unless it stops raining 
--> We won't go out if it doesn't stop raining 
2/ I will call the police unless you give back my bicycle 
--> I will call the police if you don't give back my bicycle 
3/ You won't be able to do this exercise unless your English is good 
--> You wouldn't be able to do this exercise if your English isn't good 
4/ Unless my father has enough rain, we won't grow rice 
--> If my father didn't have enough rain, we won't grow rice 
5/ The fishermen won't caught a lot of fish unless they have good nets 
--> The fishermen won't caught a lot of fish if they didn't have good nets 

If...not = unless : nếu ko

Công thức if loại 1: If + S + V(s,es), S + Will/Can/shall…… + V

Công thức if loại 2: If + S + V2/ Ved, S +would/ Could/ Should…+ V