will write and will be writing
The sentence "If I have time ,I will be writing to you tomorrow". Why we must use "will be writing" here.Can I say "will write ". What's the difference.

Question

will write and will be writing
The sentence "If I have time ,I will be writing to you tomorrow". Why we must use "will be writing" here.Can I say "will write ". What's the difference.

Answer

Personally, I would say, "If I have time, I will write to you tomorrow." By saying, "I will be writing" it seems more like you're describing the specific action of that specific time. "Tomorrow, at 2:00pm, I will be writing to you." 

I hope this helps!

Answer

Interesting question. It looks like a question of style here. There is not much difference in meaning.