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nervous; highly strung; sensitive
fussy; worried about petty things
彼は少し神経質な性格だ。
He has a somewhat nervous personality.
試験の前は神経質になりやすい。
I tend to get nervous before exams.
あまり神経質にならなくても大丈夫だと思う。
I think you don't need to be so nervous.