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to know; to be aware (of); to be conscious (of); to learn (of); to find out; to discover
to sense; to feel; to notice; to realize
to understand; to comprehend; to grasp; to appreciate
to remember; to be familiar with; to be acquainted with
to experience; to go through; to know (e.g. hardship)
to get acquainted with (a person); to get to know
to have to do with; to be concerned with; to be one's concern; to be one's responsibility
彼のことは全然知らない。
I don't know him at all.
彼は痛みを知った。
He felt the pain.
彼の苦労を知った。
I understood his hardships.