+0
An announcement in a train of my country always says as #1. I think it should be #2 because arrive is an action fisished in one moment while will be arriving can be a long time action, which begins at the time the train begins to slow down 5 kilomerters behind the terminal and ends at the time the train stops moving just at the platform of the terminal.

#1. The train will be arriving at ABC termianl at 7:00.
#2. The train will arrive at ABC termianl at 7:00.

So the train will be arriving at 6:55. It will also be arriving at 6:56,6:57, 6:58, 6:59, and 7:00. So I think the exact arrival time can't be expressed by will be arriving.

Is #1 correct? Is #1 better than #2? If it is, what feeling or meaning does it have compared with #2?
Comments  
.
arrive is an action fisished in one moment while will be arriving can be a long time action
This is not a very useful guideline, though it may be true in some cases. Both forms are fine here, but the progressive is more frequently used, to add more immediacy to the arrival; it is also more polite.
.
Mister Micawber.
This is not a very useful guideline,.

I see.

But it's still a little bit difficult to me.
May I ask a little more?

Which action or moment do you imagine to hear "The train will be arriving at ABC termianl", #3 to #6?
#3. The train has been running at full speed. But now it has just started to slow down.
#4. The train is slowing down.
#5. The train is running slowly along the platform of the terminal. The platform is passing slowly by your window.
#6. The train has just reached and stopped by the platform and its doors have just opened.
Site Hint: Check out our list of pronunciation videos.
arrive is a so-called "achievement" verb. The progressive forms of these verbs suggest that the full completion of the action of the verb is about to happen. It suggests that some event is impending, imminent.

Compare:

He is dying. = He is about to die.
He is winning. = He is about to win.
The plane [is / will be] landing. = The plane is about to land.

CJ
.
Nevertheless, these are both common announcements, with the first one the more polite:

#1. The train will be arriving at ABC terminal at 7:00.
#2. The train will arrive at ABC terminal at 7:00.


These announcements are made well before arrival, so none of your #s 3-6 apply.
.
Hi CJ,

Wooooow!!
Shock!!
But how nice!!
Gocha!!

Hi Mister Micawber,
#1 is politer and more immediate than #2. That's so important to me.

Thanks!!
Thanks!!
Thanks!!
Teachers: We supply a list of EFL job vacancies
Regarding Mr. M.'s comment about politeness:

Without the progressive, i.e., with will arrive, the statement sounds very cold and aloof to a native speaker. I can't explain it any other way. It just has no "warmth" to it the way the progressive does. That's why the progressive seems more polite.

CJ
Will arrivre is cold and aloof.
Will be arriving
is warm.

I'll never forget that.

Thanks!!