21. ---Come on, baby! You will succeed. We all wish to get good news.
----______________ , but I’ll do my best.
A. No problem. B. It is impossible. C. I can’t promise. D. Don’t worry.
22. ---Did you receive the letter the next day?
---No. Somehow, it was three weeks__________ I received it.
A. since B. when C. that D. before
