Definition: to close an entrance or container so that air or liquid cannot enter or leave it Level: C2
她密封了罐子，这样果酱就不会变质。
She ___sealed the jars so the jam wouldn't spoil.
在埃及，金字塔正在被密封，因为游客的汗水正在破坏墙上的画。
In Egypt, the Pyramids are being ___sealed, because the perspiration of the tourists was ruining the paintings on the walls.
宇航员在太空行走前密封了舱口。
The astronauts ___sealed the hatch before the spacewalk.
