A silly or foolish person.
愚かなまたは馬鹿な人。 (oroka na mata wa baka na hito)
"Don't be such an airhead, pay attention!"
"そんな馬鹿にならないで、注意を払いなさい!" (Sonna baka ni nara naide, chūi o harainasai!)
the person or thing that motivates or leads progress
to make a sincere promise
to understand the overall situation or goal
to start something from the very beginning
to explain something in simple language
to choose something after thinking about it