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問題， もんだい
1. question (e.g. on a test), problem
2. problem (e.g. societal, political), question, issue, subject (e.g. of research), case, matter
3. question (i.e. doubt)
4. public discussion, controversy
5. trouble, problem, inconvenience, difficulty
问题（例如在考试中），难题；麻烦、问题、不便、困难；问题（如社会性、政治性问题）、疑问、议题、课题（如研究课题）、案例、事项；疑问；公开讨论，争议
に
1. at (place, time), in, on, during
2. to (direction, state), toward, into
3. for (purpose)
4. because of (reason), for, with
5. by, from
6. as (i.e. in the role of)
7. per, in, for, a (e.g. "once a month")
8. and, in addition to
9. if, although
tbd