As stated in the title, I'm looking for a macro that combines every 5 sentences into a paragraph. Each sentence is separated by a paragraph break. For example:

Original article:
This is the first sentence.

This is the second sentence.

This is the third sentence.

This is the fourth sentence.

This is the fifth sentence.

New article:
This is the first sentence. This is the second sentence. This is the third sentence. This is the fourth sentence. This is the fifth sentence.

Help is greatly appreciated. Thanks in advance!