第3题: [单项选择]The prevailing wind is the wind direction most often observed during a given time period. Wind speed is the rate at which the air moves past a stationary object. A. motionless B. massive C. flexible D. noticeable 参考答案:A 答案解析:stationary固定的。A.motionless不动的;B.massive厚重的;C.flexible灵活的;D. noticeable显而易见的。