Expressing potential in Japanese isn't easy. There are many ways not exactly the same to do this, and there are restrictions on these phrases that don't exist for the English "can". In Japanese, the potential is intertwined with the concept of volition and favorability. This, not surprisingly, affects the grammar.
Normally, the potential form (可能形), is created with the auxiliary ～られる after the 未然形 for 一段 verbs and 来る. This is because a potential phrase is not something that has been done. 五段 verbs have unique potential forms. Because their origin is slightly unknown despite being so recent in origin, drop -u and add -eru and you're done! する is irregular and complicated. So, we will avoid it in this lesson.
The direct object of a potential sentence is treated as the subject of an intransitive verb. The object is still the object. が and を, though, may mark the object. There are rules behind it, but for now, we will use them interchangeably.
|五段||行く||行かれる → 行ける||行けた||行けない||行けなかった|
Part of Speech Note:For adjectives, ～られる attaches to the 未然形 of いる and いる then attaches to the 連用形 of an adjective. However, showing potential of a state with adjectives is uncommon.
Can you write Kanji?
It can't be helped, but I can't go to the park tomorrow.
Can you read a Japanese book?
Is this mushroom edible?
It's just luck that I was able to succeed at the company.
The story is too good to be true.
Can I walk there?
8. いくつまで数えられるのか。(Somewhat rude; a sense of doubt is portrayed)
How far can you count to?
Can you ride a bicycle?
Birds can fly.
Literally: Birds can fly through the sky.
You can't take Japanese at my school.
I have work tomorrow. So, I can't go.
Because we lost contact with him, we worried whether he would come back home.
I didn't have money, so I couldn't ride the bus.
Can you play the piano?
Can you come next Friday?
Our baby can already waddle around.
Can I send a fax?
Idiomatic: That's exactly it.
Word Note: See that いえる, aside from literally mean "can say", can also be used idiomatically.
20. 将棋では勝てる。 (Contrasting)
I can win at shogi.
Word Note: 将棋 is Japanese chess.
Liquor? Yes, you can drink it.
Meaning Note: In the above sentence, the potential is used in showing permission. Or, depending on context, it may refer to the liquor in question being safe to drink.
Can I drink this water?
Meaning Note: This isn't asking about the ability to drink water. Rather, it's about whether it's OK. The water could be dirty. People can still drink dirty water, but should they is the question.
Where can I park my car?
Money cannot pay for lost time.
連用形 + は+ しない is like a strong "won't" in the sense of not being able to do something.
Nobody's key will work.
Verb ＋ に ＋ Negative Potential Verb
This is an emphatic pattern used to show that even when you want to do something, you can't.
The snow piled up, and we were unable to go out (though we wanted to).
The storm is so strong that I can't even go.
More Verbs in the Potential
| Can go home||帰られる|| Can swim||泳げる|
| Can die||死ねる|| Can buy||買える|
| Can drink||飲める|| Can wait||待てる|
|Can take||取れる||Can sing||歌える|
Verbs that Cannot Have Potentials
Non-volitional verbs cannot have potential forms. This includes verbs of natural phenomenon like 降る, 光る, 流れる, and 凍る, those concerning human emotion and physiology (痛む, 痺れる (to be paralyzed), 羨む (to be jealous), any verbs that end in ある (as they have no volition), and any pattern that has no control involved like phrases with つく and いく such as 想像がつく (one can imagine) and 納得がいく (to accept as valid).
Notice that these are all intransitive verbs. However, it’s not to say that all intransitive verbs don't have potential forms. Think of motion verbs like 走る, 行く, 帰る, 戻る, 来る, etc. All of these have potentials because volition is involved in their meanings.
Set Phrase Note: あられる, the potential of ある, does happen to exist in the phrase あられもない, which means "impossible". As this is the case, it doesn't contradict what has been said above because there is no volition in impossibility.
とても in a negative sentence means "can't possibly".
I can't possibly buy something like that!
I can't possibly completely swim (that distance).
なかなか in a negative sentence means "not easily/by no means". It's used a lot with potential expressions.
There are a lot of students that are troubled at not being able to quite memorize Kanji, aren't there?
Since I couldn't easily sleep last night, today I really want to sleep and can't stand it.
I'm troubled that I can't seem to do my homework.
There are a lot of people that can't quite quit smoking even though they know that tobacco is bad.
I was troubled because I couldn't quite sleep due to jet lag.