1.If you turn off all the lights, you won't pay more money.

2.If you aren't careful, you may have an accident

3.If you don't phone your parents, you will have a trouble

4.If you stay here, you will feel safe

5.If you don't pay electricity bill today, your electricity will be cut off

6.If you don't stop smoking, your cough may be worse

7.If you do morning exercises regularly, your body will be fitter.

8.If you lock all the doors, no one can break into your house.

b)

1.If she work hard , she can pass the exam

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1. If you turn off all the lights, you will not pay more money.
2. If you are not careful, you may have an accident.
3. If you don't phone your parents, you will have a trouble.
4. If you stay here, you will feel safe.
5. If you don't pay electricity bill today, your electricity will be cut off..
6. If you don't stop smoking, your cough may be worse.
7. If you do morning exercises regularly, your body will be fitter.
8. If you lock all the doors, noone can break into your house.