题目

_______ my sister three times today but her line was always busy. A. I’d phoned B. I’ve been phoning C. I’ve phoned D. I was phoning 答案：C 解析: 全句意思为“今天我给姐姐打了三次电话，但是她的电话总是占线”。首先依据时间状语today，排除A、D两项；现在完成进行时多表示持续不断的动作，用在此处不妥。故选C项。We find ______ impossible for us to learn a foreign language well in a short time.A. that B. this C. one D. it