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question (e.g. on a test); problem
problem (e.g. societal, political); question; issue; subject (e.g. of research); case; matter
question (i.e. doubt)
public discussion; controversy
trouble; problem; inconvenience; difficulty
この問題は難しいな。
This problem is difficult.
環境問題は深刻だと思う。
I think environmental issues are serious.
何か問題があれば言ってね。
If there are any problems, let me know.