22.Lawrence Craven, a doctor from the USA,is the author of several published reports, one of______ introduced the idea in 1953 ______aspirin could reduce the risk of heart attacks.
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。 21.To this end, an all-round, balanced and effective reform of the international system is thus _______ must to prevent __________ future repeat. A.the; the B.a; the C.a; a D.the; a