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to seize; to catch; to grasp; to grip; to grab; to clutch; to hold; to catch hold of; to lay one's hands on
to obtain; to acquire; to get; to win; to capture
to understand; to grasp; to comprehend
彼の腕をしっかり摑んだ。
I firmly grabbed his arm.
チャンスをつかむのは難しい。
It's hard to seize an opportunity.
彼は手すりをしっかり摑んでいる。
He is holding onto the handrail tightly.