21. Nowadays ________ number of students with mobile phones at school ________ on the increase.
A. a; are B. a; is C. the; are D. the; is
22. If you live near the lake, _________ are that you will hear birds singing to welcome the new day.
A. possibilities B. situation C. chances D. opportunities
23. Needless to say, it takes great courage to leave a stable job and _________ one’s own business.
A. set up B. send up C. make up D. turn up
