expression, godan verb (-u)
eat a boxed lunch
A set phrase meaning to eat a packed meal, typically a bento. Often implies eating it outside the home, such as at work, school, or during a trip.
昼休みに公園で弁当を使う。
I eat my boxed lunch in the park during lunch break.
新幹線の中で弁当を使った。
I ate a boxed lunch on the Shinkansen.