What is 前に?
前に marks what happens before something else. It is the counterpart to てから, and together they let you order any two events.
With Verbs: Always Dictionary Form
This is the rule to memorise: the verb before 前に stays in the dictionary form — even when the sentence is in the past.
Verb [dictionary form] + 前に + Verb B
- 寝る前に歯を磨きます。(I brush my teeth before sleeping.)
- 寝る前に歯を磨きました。(I brushed my teeth before sleeping.)
Notice 寝る did not change. ×寝た前に is wrong. Tense is carried only by the final verb.
With Nouns: Add の
Noun + の + 前に
- 食事の前に手を洗う。(Wash your hands before the meal.)
- 会議の前に資料を読みます。(I'll read the materials before the meeting.)
With time spans, の is dropped: 三日前に (three days ago), 一年前に (a year ago).
前に Also Means "In Front Of"
Same word, spatial meaning:
- 駅の前に銀行があります。(There's a bank in front of the station.)
Context separates them easily — a place before 前に means location, an action means time.
前に vs てから
They describe the same pair of events from opposite ends:
| Sentence | Meaning |
|---|---|
| 食べる前に手を洗う | Wash hands before eating |
| 手を洗ってから食べる | Eat after washing hands |
Both are natural. Pick whichever event you want to put first in the sentence.