在发电厂和变电站中，主变压器一般选用组别是（）。
A.YN，y0
B.YN，y4
C.D，y11
D.YN，d11
参考答案：D
Mr. Liu dreamed ____ a big house for his parents after they retire.
A．to buy
B．to buying
C．of buying
D．of being buying
止吐药有哪些？为什么甲氧氯普胺具有止吐作用？
