seal-off bushing密封套管
seal sth off封锁;翻译
seal l off把……封锁起来
Seal-off密封式
lead seal pack off铅封封隔
seal-off mercury-arc rectifier封闭汞弧整流器
seal off from isolate阻隔
blockade block seal off用强制力量使与外界断绝联系或往来
fault seal off断层封堵
PHRASAL VERB（动词词组） If one object or area is sealed off from another, there is a physical barrier between them, so that nothing can pass between them. 封闭
Windows are usually sealed off.
窗户通常是封闭的。
（） →see seal