【简答题】When the old man ______ to walk back to his house ,the sun _____ itself behind the mountain. A . started had already hidden B . had started had already hidden C . had started was hiding D . was st...
【单选题】通常用加热蒸发损失百分率和加热前后针入度比来评定石油沥青的( )性质
【简答题】根据出行目的可将旅游者划分为哪几种类型?各有什么特点?
【判断题】反艺术作为一种思潮,在西方最晚可以追溯到18世纪的印象派以及同一时期法国的象征派。