操作电机车控制手柄时卡劲的主要原因可能是() 。
A.控制器转轴轴承缺油
B.卡子滚轮
C.定位弹簧丢失
D.负荷过大
参考答案:A, B, C
做人的良知就是[ ]
A.是非善恶观
B.人生观
C.正确的是非善恶观
D.价值观
----Did you ________ yourself in Beijing?
----Yes, I had _________ places of interest in Beijing.
A.have; fun to visit
B.enjoy; fun to travel
C.have; fun traveling
D.enjoy; fun visiting