遊び半分に学校へ来るな。

Meaning
don't come to school to lark around

Vocab used in this sentence

遊び
play, fun, game, playing, toy, amusement, entertainment, recreation, pastime, idling
半分
half
に
in, to, on, at, into, upon
学校
school, academy
へ
to, for, toward
来る
come, get, arrive, become, come on, come from, approach, grow
な
a, the, na, nan, nai

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