A. could have called B. might have called C. would have called D. must have called 参考答案:A 答案解析:[解析] 本句考察得是:情态动词+不定式完成式的应用,can/could,may/might,must+have+动词-ed形式用于对过去发生动作的主观判断,表示推测过去某动作“可能”、“也许”“一定
A. that B. because C. because that D. for 参考答案:A 答案解析:在用本题的句型表示“之所以……是因为”的意思时,表语从句要用that引导。但是,由于汉语的影响,初学者很容易误用because(或for)。还有人下意识地将because当做及物动词,而在其后再加th