adverbial N5 common casualpolitewritten
どうして — why
どうして
Meaning
- why? — asks for a reason or cause
Key sentence
どうして泣いているの？
Why are you crying?
Usage
A sentence-adverb, usually clause-initial; in questions it commonly pairs with the explanatory の/んです (どうして〜の？).
Examples
どうして日本語を勉強しているのですか。
Why are you studying Japanese?
どうして来なかったの？
Why didn't you come?
あの店はどうして人気があるんだろう。
I wonder why that shop is so popular.
Easily confused with
Notes
- Interchangeable with なぜ (more formal/written) and なんで (more casual) — all three mean 'why'.
See どうして in real sentences
Jengo shows どうして the way you actually meet it: inside real Japanese sentences, so it sticks instead of staying an abstract rule.
Study it in JengoSources Compiled from published Japanese grammar references.