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no good; not serving its purpose; useless; broken
hopeless; wasted; in vain; purposeless
cannot; must not; not allowed
no!; stop!
neutral point; intersection owned by neither player at the end of a game
ここに入ってはだめですよ。
You can't enter here.
だめだったらすぐ教えて。
Tell me right away if it doesn't work.
だめもとで聞いてみましょう。
I asked just in case.