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to poke (repeatedly, lightly); to nudge
to peck at (one's food); to pick at
to peck at (someone's faults, etc.)
to egg on; to put up to
子供が棒で地面をつっついて遊んでいた。
A child was playing by poking the ground with a stick.
鳥がくちばしで餌をつっついて食べていた。
A bird was pecking at its food with its beak.
隣の人に肘でつっつかれて居眠りから起きた。
I was nudged with an elbow by the person next to me and woke from my nap.