Do you go ______ a school trip ______ a museum every year?                        

Does she have any problems _________her lessons？            

Your notebook _______ Li Lei’s.

---Where is your father?
---He          to Shanghai    business.

Vienna,the capital of Austria,is  the River Danube and
The Blue Danube is      Strauss.

The students sometimes complain about their new teacher because he is too strict ____ them. 

         spending your vacation in a hotel. Why not try hiking in the country?

David scored a wonderful goal _____the football match and the team won the match ______.

When I walk_____ the classroom, all the students are listening carefully.

He had to stay at home _____________the heavy rain.
A because     B since      C because of   D so