For our next installment of seemingly simple but actually HARD words to spell in English, let’s explore: is the correct conjugation or plural of the word “fly” spelled flies or flys?
As background, I’ve been an English teacher for 18 years, and have seen these misspellings all the time with my students. The good news is that there’s a very easy answer to this spelling dilemma. In this article, I’ve illustrated the rule with my hand-drawn cartoons, in order to help you remember the spelling!
Flys vs. Flies
We know that “to fly” is a verb meaning to soar in the air or to move quickly. So do you spell the singular present tense conjugation as “time flies” or “time flys?” The answer is that it the word is always spelled “flies,” never “flys.” Yes “ie,” no “y.”
Now what about the plural of the noun, “fly,” the winged insect? (Ew, gross.) Well, the correct plural of that buzzing bug called a “fly” is also spelled “flies” — never flys. Now, just make sure you don’t flip the “l” and “i” and end up with “files” instead of “flies;” we’re not trying to do any paper sorting over here.
Flys Doesn’t Exist!
So there’s the happy news: The word “flys” doesn’t exist, and should never be used — either to conjugate the verb “to fly,” or to make the noun “fly” plural. That’s an easy enough rule to remember, right? “Flys” is just an invented misspelling, like the other fake words, “incase,” and “seperate,” and “everytime,” and “greatful” — all of which can be tossed in the trash!
Flys vs. Fly’s
Though “flys” doesn’t exist, “fly’s” with an apostrophe DOES. An apostrophe indicates either possession (belonging to someone or something), or a contraction between two words (like you + are = you’re). Let’s do some flys vs. fly’s practice.
Here is a correct example of “fly’s” for possession: “The fly’s brain (the brain belonging to the fly) is bigger than yours!” Hehe, sorry — that’s rude.
Now here is “fly’s” used correctly as a contraction: “The fly’s in the kitchen!” means, “The fly is in the kitchen!” (Want more about apostrophe use? Check out my Valentine’s Day spelling and punctuation article.)
VIDEO: How to Spell Flies
Flies or Flys, in Sum
I hope this English lesson has helped teach the blanket rule that in the “flies or flys” quandary, the correct spelling of the conjugation of the verb AND the plural of the noun is always simply “flies.” The word “flys” simply does not exist — just as the rule with “ninty or ninety,” where the former is always wrong.
Want a way to remember this? In the word “flys,” look at the “y” in the second to last letter and think, WHY did I spell it wrong? Then imagine grabbing the fake word by the handle created by the tail of the “y” and hurling it into the trash can! Wave goodbye as it FLIES through the air and lands with a plop in the rubbish bin, eaten by flies and never to be seen again.
Want more? For pairs of words that sound the same but are spelled differently — where both are actually real words, unlike “flys” — check out my giant and growing list of common homophones, with fun tricks and illustrations to help remember each! For more spelling fun, browse, “How do you spell listen?”
The author and artist, Lillie Marshall, is a National Board Certified Teacher of English who has been a public school educator since 2003, and an experienced Reiki practitioner since 2018. All art on this site is original and hand-drawn by Lillie. She launched DrawingsOf.com Educational Cartoons in 2020, building upon the success of her other sites, AroundTheWorldL.com (established 2009), TeachingTraveling.com (founded 2010), and ReikiColors.com. Subscribe to Lillie’s monthly newsletter, and follow @WorldLillie on social media to stay connected!