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expressions (phrases, clauses, etc.)
particularly, only, in the case of
Xに限って expresses an exclusive focus on X, with a negative result, impact, etc.-
夜寝れない時に限って、時計のカチカチいう音が気になるものだ。
It's only when I can't sleep at night that the ticking of the clock becomes loud enough to bother me.
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