约孕几周前后声像图上可显示胎盘（）。
A.4周
B.6周
C.9周
D.12周
E.14周
参考答案：C
既能利水渗湿，又能泄热的药物是
A．猪苓
B．茯苓
C．泽泻
D．冬瓜皮
E．葫芦
________ we stood at the top of the building, we were able to enjoy the town below clearly.[ ]
A. As
B. Although
C. Unless
D. Until
