冲积扇
参考答案：
冲积扇是河流出山口处的扇形堆积体。当河流流出谷口时，摆脱了侧向约束，其携带物质便铺散沉积下来。
Suspecting the traveler of carrying drugs, the Customs official stopped him and ______ suitcase, but found nothing at all.
A．looked up
B．went through
C．searched for
D． referred to
哪一项是心腔血栓的超声特征？（）
A.心房内团块状回声舒张期进入瓣口，收缩期返回心房
B.团块基部可见蒂状结构
C.随时间延长回声逐渐增强
D.瓣膜破坏、穿孔破裂
E.团块附着处心内膜向心室腔呈弧形突出
