用so, to , because 填空。
1. I didn't come out early, ________ I missed the early bus.
2. She went there ________ work as a librarian.
3. It was quite late, ________ we decided to go home.
4. He must be a good student, ________ he always do something well.
5. It's not difficult for you ________ learn English if you work hard in the right way.
6. I was very tired, ________ I went to bed early.
7. He bought a lot of presents _______ make his mother happy.
8. ________ something about English is one thing, and to know English is quite another.
9. He didn't come to school, ________ he was ill yesterday.
10. They are having an important meeting, ________ you can't go into the room.

Maybe I'm not very healthy, _______  I have good eating habits.  

_______ he worked hard, _______ he failed in the exam.    

- What do you think the teachers in your school are like?          
- I think they are very kind, _____ they look serious.

Maths is the subject that I'm best at, _____ it's a little boring.

-Why are you walking to school?
-______ the bus broke down on the way.  

______ Lucy got up early this morning, ______  she was late for sc.hool.       

______ it was very cold,  ______ he went out without an overcoat.