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first-year student; first-year pupil
beginner; novice; newcomer; person who has been in a role for less than a year
annual
annual plant
一年生になったよ。
I became a first-year student.
彼は元気な一年生だ。
He is an energetic first-year student.
新しい一年生が来るのを待つ。
We wait for the new first-year students to arrive.