年上 (toshiue) is a noun, and in this sentence it's used the explanatory "na no" in order to explain the fact of beeing older without giving an idea of a teacher's possession.
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年上 (toshiue) is a noun, and
年上 (toshiue) is a noun, and in this sentence it's used the explanatory "na no" in order to explain the fact of beeing older without giving an idea of a teacher's possession.