愛上某人的英文表達有fall in love with someone、have a crush on someone、be smitten with someone、be head over heels in love with someone、fall for someone等。
例如，可以說“I fell in love with you at first sight”（我一見鍾情），或者“I had a crush on her for a long time”（我很長時間內對她有迷戀）。