21. I think exercise is the ideal way to relieve ______ after a hard day.
A. version B. tension C. tense D. starvation
22. Steven’s exam results put him ______ the top ten students in his grade.
A. at B. between C. in D. among
23. —Ring me at six tomorrow morning, will you?
—Why that early? I ______.
A. will be sleeping B. will sleep C. have slept D. have been sleeping
24. You have a big mouth, Tom. You ______ have told everybody the secret.
A. can’t B. shouldn’t C. mustn’t D. mightn’t