When is <verb stem>+かける's meaning to start and leave unfinished?


I recently learned that the construction +かける means to start something, but
with an implication that the action was left unfinished:

> ビールを飲みかけたことがあるんだけど、味を全然好きなかった。
>
> "I've had a beer before, but I didn't like its taste at all." (かけた here
> tells us I did not finish the beer.)

But I've also learned that in certain cases, there is no such implication of
something being left unfinished:

> だんだん、彼の気持ちがわかりかけてきた。
>
> "I have gradually started to understand his feelings."

(This example is from maggiesensei.com)

How can I tell when a sense of incompletion is implied? Not knowing this could
lead to some confusion and poor translation.




Unfortunately your first example doesn't tell the same meaning as your
English. You have to say:

> ビールを飲んでみたことがあるんだけど、味が全然好きじゃなかった。

Plainly speaking, ～しかける has only one meaning: aborting before the action
reaches the "effective" stage. What means by "effective" is different
according to verb (see
[Aktionsart](https://en.wikipedia.org/wiki/Lexical_aspect)), and often to each
situation i.e. the moment you concern most in the action when you use the
verb. For example:

> グラスの水を飲みかけて、酒だと気づいた。  
>  _I nearly drank water in the glass when I realized it was sake._ (not
> mouthed yet)
>
> 餅を丸ごと飲みかけて、死ぬかと思った。  
>  _I all but swallowed a whole piece of rice cake; I thought I was going to
> die._ (already mouthed)
>
> 令和になったのに書類に平成と書きかけた。  
>  _I almost wrote "Heisei" into the form though it's already Reiwa._ (not put
> pen yet)
>
> 半分まで書きかけた本を完成させたい。  
>  _I want to finish my halfway written book._ (already written a lot)

From the second example in your question we can read that the speaker wants to
fully understand his feeling, and until that the "understanding" is
"incomplete". Thus the usage is valid.

On the other hand, people usually drink beverage to taste it, so it's normally
understood that 飲む is "complete" when you take in beer. It's invalid unless
you have some complicated context e.g. the speaker wants to poison the target
etc.




Unfortunately your first example doesn't tell the same meaning as your
English. You have to say:

> ビールを飲んでみたことがあるんだけど、味が全然好きじゃなかった。

Plainly speaking, ～しかける has only one meaning: aborting before the action
reaches the "effective" stage. What means by "effective" is different
according to verb (see
[Aktionsart](https://en.wikipedia.org/wiki/Lexical_aspect)), and often to each
situation i.e. the moment you concern most in the action when you use the
verb. For example:

> グラスの水を飲みかけて、酒だと気づいた。  
>  _I nearly drank water in the glass when I realized it was sake._ (not
> mouthed yet)
>
> 餅を丸ごと飲みかけて、死ぬかと思った。  
>  _I all but swallowed a whole piece of rice cake; I thought I was going to
> die._ (already mouthed)
>
> 令和になったのに書類に平成と書きかけた。  
>  _I almost wrote "Heisei" into the form though it's already Reiwa._ (not put
> pen yet)
>
> 半分まで書きかけた本を完成させたい。  
>  _I want to finish my halfway written book._ (already written a lot)

From the second example in your question we can read that the speaker wants to
fully understand his feeling, and until that the "understanding" is
"incomplete". Thus the usage is valid.

On the other hand, people usually drink beverage to taste it, so it's normally
understood that 飲む is "complete" when you take in beer. It's invalid unless
you have some complicated context e.g. the speaker wants to poison the target
etc.

