impostor|impostors

尽管升职了，他还是觉得自己是个冒牌货，配不上这个职位。

Despite the promotion, he still felt like an ___impostor unworthy of the position.

那些自称皇室成员的骗子最终被警方逮捕了。

The ___impostors who claimed to be royal family members were finally arrested by the police.

那个自称是教授的人其实是个骗子，从未上过大学。

The man who claimed to be a professor was actually an ___impostor who never attended college.