已知集合A={x|ax2+2x+1=0}． （1）若A中只有一个元素，求a的值；

泻心汤中并无止血之品，为何能主治衄、吐血证？

滋养细胞肿瘤最常见的转移部位是（）

A.肺

B. * *

C.肝

D.脑

E.骨

辩论式班会课的设计组织形式与朗诵比赛相似。

Britain occupied Java during the Napoleonic Wars. Both the British and later the Dutch tried to centralize and reform Java’s administration. The Dutch wavered between opening the area to individual enterprise and reverting to a monopoly system.

A．resolved

B．reckoned

C．hesitated

D．discriminated

下列选项中哪些属于散手比赛中的制长战术（）.

A.克制善于用手法的对手

B.克制善于用腿法的对手

C.集中力量专门进攻对方的薄弱环节

D.克制善于用摔法的对手