1. Because the weather was bad, the plane couldn't take off.
2. Because of being tired, I went to bed early.
3. Because the weather is cold, I can't go out at night.
4. Because the traffic was heavy, she went to school late.
5. Although he isn't particularly well-paid, he has a very responsible job.
6. Even though I had planned everything careful, I made some mistakes.
7. Although his health is poor, he studies very hard for the examination.
8. Although his grade was low, he was admitted to university.