で終わります: trying to close by? で帰ります, trying to leave by? It depends on the sentence?

Question

I can say 売り場は九時で終わります、 and 三時で帰ります、 which I've learned mean something like, "They'll be trying to close from," and, "I'll be trying to leave from." I've also learned that ２月２５日で帰ります is not correct. What are the rules surrounding the use of で in the place of に・から? Is there a more approximate meaning

Answer 1

で here is used as a particle to mark a time where an event terminates.

売り場は九時で終わります is a correct use of this で. (The closing(termination) of the 売り場).　

三時で行きます and　２月２５日で行きます is not correct because it's a start of something.

And for cases where に and で are interchangeable, the nuance is that the sentence with で indicates that the event lasts up to the point of the time marked by で. While the version with に just means it ends at that point.

About ~から, it means "from the point of ~". It would be more natural to say "something ends at ~" than "something ends from ~ onwards". That's why で is used over から for an event terminating.

As a side note, "trying to ~" is expressed by ~ようとする

EDIT:

In the absence of context, 三時で帰る would mean "Return (home) by means of 3 O'clock", which doesn't make sense. This で is different from the first で we initially discussed. This is the で of　"the condition/state of how the action takes place".

三時間で帰る - "Return in 3 hours time (it takes 3 hours to travel back)" would make sense.

However, in the presence of context like "ending office hours", 三時で帰る is grammatical.

Similarly, [２]{に}月{がつ}[２５]{にじゅうご}日{にち}で帰る would be "Return (home) by means of 25th February", unless context of something ending is given.

[２]{に}[ヶ]{か}月{げつ}２５日{にち} - "Return in 2 months and 25 days (it takes 2 months 25 days to travel back)" would make sense.

Now if you're trying to convey a time limit, までに is used.

３時までに帰る　- "Return home by 3 O'clock"

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EDIT2:

About 三月で私の国に帰ります. I'm not sure about this but I offer two theories:

1. It suffers the same limitation as the example discussed above. If sufficient context is given that something ends at 三月, then 三月で私の国に帰ります is grammatical. If not it becomes the で of means and sounds weird.

2. 三月 is not specific enough a time for で to be used as a marker for the time where something terminates. 三月 lasts from 一日 to 三十一日.