Breakdown of yasumi no hi ni pikunikku ni simasyou.
にni
at; on; in; to; for [indirect object particle]
〜 に する〜 ni suru
to decide on ~
休み の 日yasumi no hi
day off
ピクニックpikunikku
Nihon-shiki romanizationwatasi ha tyuugoku kara kimasita
Hepburn romanizationwatashi wa chuugoku kara kimashita
