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。
例：It is generally considered unwise to give a child he or she wants .
A．however B．whatever C．whichever D．whenever
答案是B.
21. The wild flowers looked like a soft orange blanket______, the desert.
A. covering B. covered C. cover D: to cover
22. In review of 44 studies, American researchers found that men and women who ate six key foods daily cut the risk of ______ heart disease by 76%.
A. a; the B. the; a C. a; 不填 D.