头车车钩中心高度由于车钩整体超差，可通过空气弹簧进行调整。（）
参考答案：对
129. After a long riding, the passengers in the bus were very tired and some of them ____ asleep.
A．went to
B．fell
C．put to
D．Became.
我国已进行（）次全国营养调查。
A、3次
B、4次
C、5次
D、6次
