familiar [fəmɪljɚ] adj. 熟悉的（be familiar with N. 指「對……很熟悉」）
I am not familiar with the band you are talking about.
我對你提到的樂團並不熟悉。

mental [mɛntḷ] adj. 心理上的；精神上的；智力的
Ken likes to do puzzles because they are a good form of mental exercise.
肯恩喜歡玩猜字謎，因為那是一種很好的智力訓練。