凡庸 ぼんよう愚昧 ぐまいでしょう
bon'yō gumaideshō

Noun
Desu Copula
na-Adjective
no-Adjective

Expresses probability in a polite manner ("probably…") of 凡庸愚昧

1. Probably ordinary and foolish.; Probably commonplace and ignorant.

Polite
Presumptive
Conjecture