Have you ever read a list and felt slightly confused? It was all there, but it just wasn't "quite right."
That's probably because the writer failed to use parallel language.
OK – what the heck is that?
Simply put, using parallel language means making a list in which each item is given in the same form of speech. All nouns, all verbs, all adjectives, etc.
Here's an example in which the writer used non-parallel language:
"As your listing agent, my service includes tips for giving your home more appeal, taking professional photographs, and available 24 hours a day."
It's there, but it's lumpy and disjointed.
He should have said "My service includes providing you with tips for giving your home more appeal, taking professional photographs, and being available to you 24 hours a day."
How about a list of home features: "This home offers panoramic views, recently painted, and your cook will love the kitchen."
Again, the information is there, but it's lumpy. Sort of like driving on a bumpy road.
Change that to "This home offers panoramic views, fresh paint, and a kitchen that your cook will love."
Our goal as writers should be to get our message into the minds of our readers without them having to think about the words we used.
So – avoid lumps and bumps. Check your lists to make sure all the words and phrases are parallel.