Until, by, while still
Clauses that mark the edges of a time window: until, by, and while the window is still open.
-made
until
〜まで
Means 'until' after a dictionary-form verb or a time word (kuru made matsu, ashita made). It pairs with kara for ranges and also means 'as far as' a place.
kaeru made matteru ne.
I'll wait until you get back.
帰るまで待ってるね。
kaeru made mattemasu ne.
I'll wait until you get back.
帰るまで待ってますね。
The action fills the whole span. For a deadline, use -made ni.
Learn alongside: -made ni
-made ni
by (a deadline)
〜までに
Sets a deadline: the action happens once, some time before X (ashita made ni okuru).
kaeru made ni wa owaru yo.
It'll be done by the time you're back.
帰るまでには終わるよ。
kaeru made ni wa owarimasu yo.
It'll be done by the time you're back.
帰るまでには終わりますよ。
Quick test: if English says 'until', use made; if it says 'by', use made ni.
-uchi ni
while still; before it changes
〜うちに
Says to act while a condition still holds (atsui uchi ni, wakai uchi ni). With a negative, -nai uchi ni means 'before X happens'.
atsui uchi ni tabete.
Eat it while it's hot.
熱いうちに食べて。
atsui uchi ni tabete kudasai.
Please eat it while it's hot.
熱いうちに食べてください。
Don't hear it as uchi ni ('to home'). Here it follows a verb, an adjective, or noun + no. ima no uchi ni = while you still can. -teru uchi ni = while doing X, before you knew it (hanashiteru uchi ni kuraku natta).