第二部分英语知识运用（共两节，满分45分）
第一节 单项填空（共15小题；每小题1分，满分15分）
从A、B、C、D四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
21．Most construction workers can earn over two thousand RMB _____ month but usually they get their wages by _____ year.
A. the; the B. a; the C. the; a D. a;a
22. --- Mum, where are my gloves? Is the pair of gloves ______ mine?
--- Yes. You have to wear another pair.
A. washing B. have washed
C. having washed D. being washed
23. Some groups still have difficulties______ access _______ social services.
A. gain; in B. gaining; to C. to gain; to D. gaining; of
