When you want to finish a letter or a book you roll up the scroll and then you put a wax seal at the end of the roll and that seals the book.

当你看完一封信或一本书时，就将书卷卷起，然后在末端用蜡封印，将书封起来。

youdao

The sealing strips seal the suction zones towards the roll interior where no vacuum is created.

密封条用于密封朝向（非真空的）辊内部的抽吸区。

youdao

Then roll the edges, pinching them to seal.

擀开边缘，再揑紧封口。

youdao