Unless-If not
1.If it doesn't rain , we can play tennis
->Unless it rains , we can play tennis
2.If you are not careful , you will cut your self with that knife
->Unless you are careful , you will cut your self with that knife
3.If she doesn't hurry , she will be late
->Unless she hurries , she will be late
4.If they don't come early . I'll not give them that report
->Unless they come early ,I'll not give them that report
5.If you don't drive more carefully , you will have an accidents
->Unless you drive more carefully , you will have an accidents