既…也…grammar point · tier 2 · additive coordination 既…也… (both … and …)
Stacks two facts that hold of one subject at once: 既 sets the first as a given, 也 adds the second alongside it.
字源 FORM what the parts do
既 is the meal-done graph (皀 the bowl, 旡 the person turned from it, full) — it lays down A as a settled given about the subject. 也 says also, and adds B as a second fact about that same subject. The thing they share sits before 既; what 既 and 也 each carry are the two facts true of it together.
故事 STORY a scene to remember it by
One thing on the table. 既 sets the first card down beside it, face up; 也 lays a second card on the same spot. Both cards belong to the one thing.
字源記憶法
框 · Frame
[subj] 既 [fact A] ，也 [fact B]
觸 · Trigger
Two compatible facts hold of the same subject and you want both on show, the second adding to the first.
序 · The move
1Fix the one subject both facts describe; it goes before 既.Is A about the same thing as B? If they describe two different subjects, this frame does not fit.
2Put the first, given fact after 既.Does A read as settled, not as a turn against B?
3Add the second fact after 也, parallel in shape to A.Do A and B stack as compatible pluses (additive), not clash (contrast)?
例 · Examples
1來臺灣既jì — sets the first given fact可以學中文，也yě — adds the second fact alongside可以享受美食。
Coming to Taiwan, you can both learn Chinese and enjoy great food.
既…也… stacks two compatible facts on one subject (additive); 雖然…但是… turns against expectation (concession). 既 adds, 但是 reverses.
又…又…
Both coordinate two facts of one subject. 又…又… is colloquial and leans on concurrent traits (又高又帥); 既…也… is more written and treats A as an already-given the second fact joins.
既然…就…
Same 既, different job: 既然…就… is a conjunction reasoning from a given to its consequence (since A, then B). 既…也… coordinates two parallel facts of one subject — no cause runs between them.
✗ 他既高，但是很瘦。 → ✓ 他既高，也很瘦。 (additive frame takes 也, not the contrastive 但是)
✗ 既下雨了，我也帶傘。 → ✓ 因為下雨了，所以我帶傘。 (既…也… coordinates two facts of one subject; for cause→effect use 因為…所以…)
✗ 這家店既便宜。 → ✓ 這家店既便宜，也好吃。 (既 opens a pair; the 也 half must close it)
English 'both … and …' lets the two halves take different subjects ('the food is cheap and I'm full'); 既…也… needs one shared subject before 既, with both facts predicated of it.