A submarine glided silently through the water.

一艘潜艇无声中滑行。

Within a short time, everything on the submarine was buttoned up.

不一会儿, 潜艇内所有的东西都扣紧了。

A submarine surfaced outside the harbor.

潜艇港外到面。

The submarine signaled for help.

潜艇发出求救的信号。