题目

—I called you at 6 o'clock yesterday evening, but nobody answered.— I'm sorry. I          my friend download the movie Kung Fu PandaⅡwhen the telephone rang,A. would help     B. helped    C. was helping 答案：C解析:考查动词时态 上下语境都是过去时，这里强调电话响时我正在帮助，所以用过去进行时。3千克水和3克药粉配成药液，药粉和水的比是（ ）A．1：1 B．100：1 C．1：1000 D．1：1001