题目

① 计算：②解不等式组：  答案：略解析:①解：原式＝9+－1……………………………3分         ＝7+……………………………… 4分②解：解不等式①得  ，解不等式②得  ．所以原不等式组的解集为．………………4分 The boy is only five years old, but he is quite used          the telephone. [     ]A. to answer     B. to answering     C. of answering    D. by answering