以後grammar point · tier 1 · 以後 after (a time or event)
Postposed time-relator: marks everything downstream of the point named before it.
字源 FORM what the parts do
以 grips the point just named and holds it as the anchor. 後 is the trailing foot (夂) on the road (彳), the late one, and tags the event onto the far side of that anchor.
故事 STORY a scene to remember it by
A post stands in the road. A walker passes it and keeps going; every step out beyond the post falls on the far side. The ground behind the post is sealed off.
字源自撰記憶法
框 · Frame
[clause / time-span] 以後，[later event]
觸 · Trigger
You have an anchor point — an event done or a span of time — and the thing you are saying comes later than it.
序 · The move
1name the anchor first: the finished event or the time-spandoes the anchor land before 以後, not after it?
2close it with 以後is 以後 at the tail of the anchor clause, postposed?
3state the later event in the main clause that followsdoes this event sit past the anchor in time, not before it?
例 · Examples
1吃完finish eating早餐breakfast以後after，他就then (right after)去上學go to school了。
After he finished breakfast, he went off to school.
以後 only orders the events as later; 一…就… clamps them tight, the second firing the instant the first lands.
以後 in front of the anchor: 以後吃完早餐 → 吃完早餐以後
after used for before: 來日本以後我學了中文 (meaning prior) → 來日本以前我學了中文
English word order for the span: 以後兩個月 → 兩個月以後
English puts 'after' in front of its clause (after breakfast); Chinese postposes 以後 to the tail (吃完早餐以後). Time-spans also flip: '(in) two months' becomes 兩個月以後, span first.