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more or less; though not quite satisfactorily; after a fashion; pretty much; roughly; so far as it goes; technically
tentatively; for the time being
just in case
once
一応準備は終わりましたが心配です。
I have more or less finished preparing, but I am worried.
重要な書類なので一応確認しておいたほうがいい。
You should confirm just to be sure.
一応説明しましたが理解されたかな。
I explained for now, but I wonder if it was understood.