空く
あく
to open, to become empty (vacant)
Aku (空く) is a godan verb meaning "to open, to become empty (vacant)". Its polite form is 空きます (akimasu), its te form is 空いて (aite), its past form is 空いた (aita), and its negative form is 空かない (akanai).
Godan verbJLPT N4
Aku (空く) conjugation quick reference
空く means "to open, to become empty (vacant)". Its main forms are listed below, with links to the grammar pattern behind each form.
Aku example sentences
席が空いています。
The seat is available.
昨日、この店は空いていました。
Yesterday, this shop was open.
今、時間が空いていません。
I don't have free time now.
How to use Aku: grammar notes
•空く (あく) is often used with が to show that something becomes open or available — for example, 席が空きました ("A seat became available").
•Don’t confuse 空く (あく, to become open) with 開ける (あける, to open something) — 空く happens on its own, while 開ける is something you do.
•When asking if something is available, like a room or seat, you can say 空いていますか？ (Is it available?), but avoid saying 空けていますか？ which would be incorrect.
•JLPT N4 level
Common phrases with Aku
席が空く（せきが あく）
A seat becomes available
お腹が空く（おなかが すく）
To get hungry
時間が空く（じかんが あく）
To have free time / to become available
Aku (空く) conjugation table
| Form | Japanese | Romaji |
|---|---|---|
| Basic Forms | ||
| Dictionary Form | 空く | aku |
| Masu Form | 空きます | akimasu |
| Te Form | 空いて | aite |
| Past Form | 空いた | aita |
| Negative Form | 空かない | akanai |
| Past Negative | 空かなかった | akanakatta |
| Polite Forms | ||
| Polite Present | 空きます | akimasu |
| Polite Past | 空きました | akimashita |
| Polite Negative | 空きません | akimasen |
| Polite Past Negative | 空きませんでした | akimasendeshita |
| Advanced Forms | ||
| Potential Form | 空ける | akeru |
| Passive Form | 空かれる | akareru |
| Causative Form | 空かせる | akaseru |
| Causative Passive | 空かされる | akasareru |
| Volitional Form | 空こう | akou |
| Imperative Form | 空け | ake |
| Conditional Forms | ||
| Conditional (ば) | 空けば | akeba |
| Conditional (たら) | 空いたら | aitara |
| Other Forms | ||
| Progressive Form | 空いている | aiteiru |
| Desire (たい) | 空きたい | akitai |
| Prohibition | 空くな | akuna |