Travelers , however , still nervously watch the loose rock on the mountainside s because small landslide s frequently bury sections of the road causing delays of several hours 不过旅人仍会紧张地留意山坡上松落的岩石，因为轻微的山崩常会阻断道路，延误通行好几个小时。
2.
Threaded seat rings for valves in services with high velocity ( turbulent ) flow or thermal cycling should be lock welded to the body to avoid loosening . please specify 如果阀门用在高速流体(湍流)或热循环应用环境中，则螺纹阀座环应该锁焊到阀体上，避免松落。请在订购时加以指定说明。
