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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
彼は箸でおかずをつつくだけだった。
He just poked at the side dishes with his chopsticks.
スズメが米粒をつつく音が聞こえた。
I heard the sound of sparrows pecking at grains of rice.
指で肩をつつくのはやめてほしい。
I wish you'd stop poking my shoulder with your finger.