Koto ga dekiru vs. Potential Form of Verbs (meanings)

[cultureman22]

To whom it may concern,

I am having trouble using the right one.

I know that koto ga dekiru is formal and used in writings while potential form of verbs are for daily conversations.

However, I need some guidelines that can tell me the difference in their meanings.

For example

taberareru vs. taberu koto ga dekiru

There has to be a slight difference in their meanings because my Japanese professor always tells me to use koto ga dekiru, and some of the potential form of verbs can't be used like for owaru, wakaru, and etc.

Oh by the way, do we always use koto ga dekiru with our professors and superiors?

Please help. This has been bothering me a lot.

[Spongebo]

So i'm no guru, but here's what i understand about the verb forms aforementioned.

Simple Answer:

I was talking to a japanese friend of mine and when I asked her this she asked me what the difference between "can" and "am able to" was. I think it is a similar situation in Japanese.

taberareru = I can eat
taberu koto ga dekiru = I am able to eat (The thing of eating I am able to do)

In terms of politeness, as long as you made taberareru into taberaremasu, it would be just as polite as taberu koto ga dekiru. (I guess in writing formally, you might put taberu koto ga dekiru). Now there are a few reasons your prof. might want you to say taberu koto ga dekiru (1. he might be old school and very formal (as most are) 2. He might not want you to confuse potentiality and passivitiy). I took some time to write up a little (or a lot) on the subject below, if you're interested take a read, it might help clear some more complicated questions up, but what is above is pretty much the simple answer to your question: "can" and "am able to".


So for a more detailed version:

taberu koto ga dekiru = taberareru (much more commonly heard is tabereru (take out the ra) which means the same thing. So for your japanese friends, most would say tabereru) - to make it more polite, seeing as it does end in ru, you can always add the masu stem. So taberaremasu (again, a mouthful, so taberemasu).

*Be careful though, ichidan verbs (those taberu=tabemasu) are not plug and chug. For example, miru (to see) becomes mieru and not mirareru (concerning potentiality! mieru = miru koto ga dekiru) There are a few of them that do this, it just takes some memorization and practice though.

For yodan verbs (those NOT taberu = tabemasu i.e. yomu, iku...etc) you can change the ending to e (yome, ike) and add ru on the end to express the same meaning.

yomeru/yomemasu = yomu koto ga dekiru
ikeru/ikemasu = iku koto ga dekiru and so forth.

Here is a page that might help a little http://www.timwerx.net/language/jpverbs/lesson51.htm.

Laslty, the reason your professor might insist is because taberareru is technically the passive form of the verb. like "to be eaten." (see below if interested) It also is technically a more honorific form of the verb tabemasu (store clerks at times will use it, not as a potentiality, solely on honorific terms...weird right?) To be safe (and to keep your grade!) I would use the koto ga dekiru as your teachers requests (you may ask him/her if there is a reason behind this), but for normal life, you can just use tabereru.

Not to make it more difficult, but if you're interested.

Ichidan verbs
taberu = (passive) taberareru 'to be eaten"
miru = (passive only!!) mirareru "to be seen"

Yodan verbs
kau = (passive) kawareru "to be bought"
yomu = (Passive) yomareru "to be read"

Sorry for the long response, I hope this helped![/i]

[QuackingShoe]

*Be careful though, ichidan verbs (those taberu=tabemasu) are not plug and chug. For example, miru (to see) becomes mieru and not mirareru (concerning potentiality! mieru = miru koto ga dekiru) There are a few of them that do this, it just takes some memorization and practice though.

They are plug and chug. Potential 見られる exists, and means something separate from 見える (見える is about an object being visible, while 見られる is about an object being possible to see). The same is true of 聞ける vs 聞こえる. That is, 見える and 聞こえる are more used for things that are just around you and that you would see/hear even if you didn't notice them, or in any way want/try to see them. They describe what's *perceptable*. Neither are a form of 見る/聞く, they're separate words entirely.
A really easy example of when to use 聞ける etc instead is when talking about what you can/can't do with electronic devices and the like. ラジオの聞ける携帯.


To the OP: I have no particular idea why your teacher would insist on one. Ask?

[cultureman22]

Thank you so much for your help! I really appreciate it.

One of my questions is still unanswered.

My professor told me that I cannot use the potential form for all verbs. I already know about miru, but what about other verbs?

For example,

"owareru" - My professor told that it is a bad word.

Anyways, I know that potential form is not simply plug and chug...

Sorry if I have been annoying about this.

[mieth]

I think your issue with this is because owaru is an intransitive verb. koto ga dekiru or the potential form of verbs with action need to be transitive.

[cultureman22]

OHH!!! I GET IT! FINALLY!

THANK YOU EVERYONE FOR YOUR HELP!

[cameljones016050]

Sometimes potential is already built into the word. Wakaru - either you understand or you don't. There are ways to get around it, like ~you ni, but other times it's out of you control completely.

Nihongo ga wakaru you ni... In order to understand Japanese.... (There are things one can do to understand Japanese: read, listen, study, etc..)

XXAme ga yameru you ni... In order to make it stop raining... (There is nothing you can do to make rain stop. No potential form, no ~you ni construction) XX

A few more that can't take a potential form and a few irregular:

To exist: Aru - arieru
To begin: (intrans): Hajimaru - you ni
To bloom: Saku - it happens or it doesn't
To clear up: (of the weather) Hareru - it happens or it doesn't
To be closed: Shimaru (intrans) - you ni
To decrease: (intrans) Heru - you ni
To get fixed/well: (intrans) Naoru - you ni
To grow/be raise: (intrans) Sodaru - you ni
To need Iru: you need it or you don't
To open: (intrans): Aku - you ni
To rain/snow: Furu - it rains/snows or it doesn't
To ring (intrans): Naru - you ni
To stop (of rain, etc.) (in trans): Yameru - it will or it won't
To take (time): Kakaru - it takes a certain amount of time or it won't
To understand: Wakaru - you ni

There are more. This list pretty much all came from "Japanese Sentence Patterns for Effective Communication" by Taeko Kamiya