supposed

v. 假定(必须以...为条件)
a. 想象上的

The supposed beggar was really a police officer in disguise.

那个众人眼中的乞丐，其实是化了装的警察。

We are supposed to dress up as movie characters for the party, what a novel idea!

我们在晚会上要装扮得像电影中的角色，这是一个多么新奇的主意啊！