必要时罐式飞机加油车油罐可以提前清洗。
参考答案:对
He often rides a bike to school, but I _____ to my school. [ ]
A. by bus
B. on a bus
C. take a bus
驱动桥磨合试验时,允许有均匀的齿轮的啮合声,但不允许有敲击声或高低变化的响声。()