共发射结放大结，反馈信号直接接到三极管基极的反馈是并联反馈。
参考答案：对
--- They are quiet, aren’t they?
--- Yes. They are accustomed ____________ at meals.
A．to talk
B．to not talk
C．to talking
D．to not talking
最有可能的诊断是
A．急性阑尾炎
B．美克尔憩室炎
C．粪石性肠梗阻
D．肠旋转不良
E．粘连性肠梗阻
