in (或 for) perpetuity

forever

永遠(yuǎn)地

all the Bonapartes were banished from France in perpetuity.

所有波拿巴家族的人都被永遠(yuǎn)逐出法國。

in perpetuity

For an indefinite period of time; forever.

永遠(yuǎn)：持續(xù)一個(gè)無限期的時(shí)間段；永遠(yuǎn)