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thoughtlessly; rashly; unwisely; half-heartedly
halfway; half-done; incomplete
なまじ知識があるせいで迷った。
Having half-baked knowledge made me hesitate.
なまじ期待したから落胆が大きい。
The disappointment was greater because I rashly got my hopes up.
なまじ手を出さない方がよかった。
It would have been better not to get involved rashly.