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dull; uninteresting; boring; tedious
insignificant; unimportant; trifling; trivial; worthless
absurd; foolish; silly; stupid
useless; pointless; disappointing
詰まらない本だった。
It was a boring book.
詰まらなくて寝てしまった。
It was so boring I fell asleep.
詰まらない話で時間が無駄になった。
Boring talk wasted my time.