to improve one’s skill or knowledge
誰かのスキルや知識を向上させる (sude ni mananda chishiki ya sukiru o kōjō saseru koto)
"She decided to brush up on her painting techniques."
"彼女は自分の絵画技術を向上させることに決めました。" (Ōkina kaigi no mae ni, watashi wa purezentēshon sukiru o **brush up on** suru hitsuyō ga arimasu.)
to suddenly make a lot of money
to contribute money or effort to a shared goal
to form new friendships
to plan a new direction or strategy
someone who acts independently and ignores rules
unexpectedly or without warning
