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to be strongly attracted (by); to be utterly charmed (by); to be completely captivated (by); to admire greatly; to fall deeply in love (with); to fall head over heels (for)
彼は彼女にすっかり惚れ込んだ。
He completely fell for her.
彼女はそのデザインに惚れ込んで即買いした。
She was so taken with the design that she bought it on the spot.
ベテラン監督は才能ある若者に惚れ込みがちだ。
The veteran coach tends to fall hard for any young athlete with unusual talent.