Viết lại câu sao nghĩa không đổi

1.we shouldn't make too much noise because the baby will wake up
-> If
2.it's raining heavily, so we can' t go out
-> If
3. he bought this car because of its low pric
-> if
4. He bought this car because its price is low.  If
5. I don’t have a computer, so I can’t get more work done.  If
6. People don’t understand you well because you don’t speak clearly.  If
7. People don’t save much money because they smoke.  If