2:1房室传导阻滞是二度Ⅱ型的一种特殊类型。()
参考答案:错
Eating much junk food _____ your health.[ ]
A. is good for
B. is good to
C. is bad for
D. is bad to
在CD-I系统中。每个CD-I光盘最多含有99个光道,CD-I光盘按光道信息类型分为2种CD-I光盘,分别为?