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1年生, 一年生, いちねんせい
1. first-year student, first-year pupil
2. beginner, novice, newcomer, person who has been in a role for less than a year
3. annual
4. annual plant
一年级学生;一年生植物
は
1. indicates sentence topic
2. indicates contrast with another option (stated or unstated)
3. adds emphasis
指示句子的主题;表示与另一选项(无论是否明确提及)形成对比;表示强调