in a ... guise

1. 以……的外表

He is an enemy in a friendly guise.

他是个装扮成朋友的敌人。

in the guise of

1. 装扮成

A man appeared at the castle gate in the guise of a woodcutter.

有个人装扮成樵夫的样子出现在城堡大门口。

under the guise of

1. 假借

A lot of nonsense was talked, under the guise of philosophy.

假借哲学的名义讲了一大堆的废话。