Ngu dốt, dốt nát

Không biết

to be ignorant of (in)...

không biết gì về...

Bất lịch sự vì chẳng biết thế nào là lịch sự

adjective

apprenticed , benighted , birdbrained , blind to , cretinous , dense , green * , illiterate , imbecilic , inexperienced , innocent , insensible , in the dark , mindless , misinformed , moronic , naive , nescient , oblivious , obtuse , shallow , thick , unconscious , unconversant , uncultivated , uncultured , uneducated , unenlightened , uninformed , uninitiated , unintellectual , unknowledgeable , unlearned , unlettered , unmindful , unread , unschooled , unsuspecting , untaught , untrained , unwitting , witless , uninstructed , backward , primitive , unacquainted , unaware , unfamiliar , unknowing , callow , charlatanic , green , inerudite unenlightened , quackish , stupid , uniformed , unskilled , untutored , young

adjective

aware , competent , educated , intelligent , knowledgeable , literate , talented , wise , instructed , learned , proficient , schooled , trained