What's the difference

[deeppra]

Dear Members,

What is the difference between:
"I will come late today" and "I will be coming late today".

Best Regards

[Doran]

The meaning is the same.

[David L.]

Then why do we need a Progressive form of the tense if they mean the same?

[engee30]

Then why do we need a Progressive form of the tense if they mean the same?

There are two substantially different uses of the Future Continuous tense. One is for single actions, and the other for continuous ones.

Single actions
We use will be + an ing-form for an action which will happen in the course of events because it is part of a plan or part of a schedule of future events:
The party will be starting at ten o'clock. (part of the evening's events)
The ship will be sailing soon. (part of our journey)

We also use a future continuous form for things that will happen as part of a routine. This sub-use is similar to the one explained above:
I'll call in and see you tomorrow afternoon. I'll be passing your house. It's on my way home from work.
Trevor and Laura will be cleaning the house tomorrow. They always do it on Saturday.

Another sub-use of the Future Continuous is to ask about someone's plans:
A: Will you be going anywhere near a chemist's this morning?
B: Yes, why?
A: Could you get me some aspirin, please?
B: Yes, of course.

Continuous actions
We use will be + an ing-form for an action over a period of time.
It means that at some time in the future we will be in the middle of an action:
Andrew can't go to the party. He'll be working all day tomorrow. (there will be a moment tomorrow when we will be going out to the party - Andrew will be working at the time)
I'll be out at three o'clock. I'll be playing golf.
When the men leave the building, the police will be waiting for them. (the police will start waiting for them before the men leave the building)
What will we be doing in ten years' time, I wonder?

[David L.]

Frankly, I can't see the difference between:
"Single action":
The party will be starting at ten o'clock.
"Continuous actions":
He'll be working all day tomorrow.
...with regard to tense.
Can anyone clarify for me?

...and by the way, I thought the original question was:
What is the difference between:
"I will come late today" and "I will be coming late today".
- two different tense forms.

[engee30]

Frankly, I can't see the difference between:
"Single action":
The party will be starting at ten o'clock.
"Continuous actions":
He'll be working all day tomorrow.
...with regard to tense.
Can anyone clarify for me?

Will be starting is not so much extended in time as will be working is. That's why the former is considered as referring to a single action, whereas the latter is not.

[David L.]

Where did 'starting' come into it? The thread posting, and given sentences were:
What is the difference between:
"I will come late today" and "I will be coming late today".