题目

The old man starts ________ sports at five every day.A. playing B. playsC. played D. play 答案：【答案】A【解析】句意：这个老人每天5点开始做运动。根据start doing sth开始做某事；故选A已知sina=32，且a是锐角，则a=（　　） A、75°B、60°C、45°D、30°