路基及其排水、防护和加固设备，应符合《铁路路基大维修规则》的规定，并保持畅通和完好状态。
参考答案：错
蛲虫的主要临床表现是（）.
A.腹痛
B.腹泻
C.贫血
D.便血
E.肛门瘙痒
14. Over the long process of evolution, animals have developed their ______ senses, which makes it possible for them to _____ their environments.
A．specially; conquer
B．unique; survive
C．uniquely; survive
D．special; exist
