最常合并重症肌无力表现的纵隔肿瘤是
A．胸腺瘤B．胸骨后甲状腺肿C．畸胎瘤D．支气管囊肿E．神经源性肿瘤
参考答案：A
Computer knowledge will become the ability to read and write. [ ]
A. a requirement so basic as
B. as a basic requirement as
C. as basic a requirement as
D. so basic a requirement as
当一只电容器的额定工作电压值太小不能满足需要时，可采用电容器（）的方式来获得较高的额定工作电压。
A、并联
B、串联
C、混联
D、串并联
