tube door

例句：

1. 1. The new elevator hasa tube door that opens up to thelobby.
   新电梯有一个管状门，可以通往大堂。
2. 2. The old house hada tube door that was difficult to open.
   旧房子有一个管状门，很难打开。
3. 3. The engineer used a tube door toseal off the leaky pipe.
   工程师使用一个管状门来密封那个漏气的管道。