润滑油温过高，可能是（）引起的。
A.滤油器太脏
B.油压表失灵
C.吸油管不严
D.润滑油供应不足
参考答案：D
降糖药苯乙双胍（降糖灵）属于（）
A.双胍类口服降血糖药
B.预混胰岛素制剂
C.磺酰脲类口服降血糖药
D.α-糖苷酶抑制药
E.普通胰岛素
In Township K, of the housing units are equipped with cable television. If of the housing units, including of those that are equipped with cable television, are equipped with videocassette recorders, what fraction of the housing units have neither cable television nor videocassette recorders ？（）
A.A
B.B
C.C
D.D
E.E
of the housing units are equipped with cable television. If 
of the housing units, including 
of those that are equipped with cable television, are equipped with videocassette recorders, what fraction of the housing units have neither cable television nor videocassette recorders ？（）