1. Because he was busy, he couldn't meet you
2. Because she was sick, she went to bed early
3. Because the test was so difficult that nobody can do it
5. Because the road is narrow, the two cars can't passed each other
6. Because of her oldness, she can't work hard
7. Because of his poorness, he couldn't go to school
8. He likes her, because of her beauty
9. He broke the vase, because of his carelessness
10. We can't go for a walk, because of the heavy rain
