1、  Where is the headquarter?

2、 The article ________ on this subject was written by Mr. Black.

3、  How about having a picnic on Sunday?

4、  I am so sorry for having kept you waiting for so long.

5、  —I can’t find my handbag!

6、 ________ a teacher and some students in the classroom.

7、  阳虚便秘的茶饮配方中，主要使用的药材是？（ ）

8、  He is so careful to _________ there are no mistakes in his homework.

9、（填空题）  Mark Twain was a well - known American writer.【改】Mark Twain was ___________ his American novels and stories.

10、  Excuse me, can I pay in cash?

11、  Mary as well as her sister _________ listening to music.

12、  The place has _________ into one of the most beautiful tourist spots in the city.

13、  The bus __________ yesterday.

14、  My father has worked in the factory _________ he was 20 years old.

15、  I’ll have to miss your wedding this Sunday.