20. --- Will you do me a favor?

　 --- Yes.________.

A. I will　　 B. I’m glad to　　 C. I can　　　　 D. I must

19. Poor _____ he was, he never gave up and worked to make his own career.

　　　 A. although　　　　　　　　 B. as　　　　　　　　　　　　　　　 C. since　　　　　　　　　　　　 D. while

18. By no means _______ promised to keep you ________of how their business was going on.

　　 A. he has; informing　　　　　　 B. he has ; informed

C. has he; informing　　　　　　 D. has he; informed