21. —Putting on a happy face not only helps us make friends but also makes us feel better.

A. I’m with you on that   B. I’d love to                C. It’s up to you        D. It’s my pleasure

22. When he ______ the door, he found his keys were nowhere.

A. would open            B. was to open         C. had opened           D. opened

23. One evening, I was with my friend Auguste Dupin at his house in Paris when he had a visit _____ Georges Godinot, head of the Paris Police.

A. at                           B. from                       C. to                                  D. with