包绕羊水的薄膜是
A．胚外体腔
B．卵黄囊
C．羊膜
D．绒毛膜
E．底蜕膜
参考答案：C
Does he go to school by bus?[ ]
A. Yes, he do.
B. Yes, he does.
C. No, he does.
与内湿的形成关系最密切的脏是：
A．心
B．肝
C．脾
D．肺
E．肾
