Complex sentence: Filling in the edit summary field greatly helps your fellow contributors in understanding what you changed, so please always fill in the edit summary field, especially for big edits or when you are making subtle but important changes, like changing dates or numbers.
Split into simpler sentences: Filling in the edit summary field greatly helps your fellow contributors in understanding what you changed. So please always fill in the edit summary field, especially for big edits or when you are making subtle but important changes, like changing dates or numbers.