()ける

あける
verb (ichidan)
to open
他動詞 transitiveaction
See also: () (intransitive)
Conjugation
AffirmativeNegative
Present()ける()けない
Present polite()けます()けません
Past()けた()けなかった
Past polite()けました()けませんでした
て form()けて()けなくて
ている present()けている()けていない
ている polite()けています()けていません
ている past()けていた()けていなかった
ている past polite()けていました()けていませんでした
Conditional ば()ければ()けなければ
Conditional たら()けたら()けなかったら
Volitional()けよう
Volitional polite()けましょう
Potential()けられる()けられない
Passive()けられる()けられない
Causative()けさせる()けさせない
Imperative()けろ()けるな
1. to open
To cause something closed to become open. A transitive verb - you open something. The intransitive pair is ()く (aku).
Please open the window.
ドア()ましょう
Shall I open the door?
Please try opening the gift box. What do you think is inside?
てみる = try doing
It's hot, so may I open the window? There's no air conditioner, so I want to let in the breeze.

Transitivity: 他動詞(たどうし) (transitive). Pair: () (intransitive, to open by itself). Pattern: X()ける.

Aspect:いる indicates resulting state. ()いる usually means 'have opened (and it's still open)' rather than 'is opening.'

Common patterns

Opposite: ()める (to close something).

Confusable: ()ける vs (ひら), which are written with the same kanji but are not interchangeable. Use ()ける for things that swing, slide, or come apart to leave a gap: (まど), ドア, lids, and containers. Use (ひら) for things that unfold or spread out, and for holding an event: (ほん)(ひら) (open a book) is standard, while (ほん)()ける is not said.