Flys or Flies? Understanding the Difference and Proper Usage

The English language can be tricky, especially when it comes to words that look alike but have different meanings or forms. One such pair is “flys” and “flies.” Is it “flys” or “flies“? Understanding the correct usage of these two terms will help ensure that your writing is both clear and grammatically correct.

In this article, we’ll dive into the differences between flies and flys, the correct usage in various contexts, and common scenarios where these words appear.

Whether you’re writing a quick email, creating content for a blog, or just trying to improve your grammar, this guide will clear up the confusion once and for all.

Flys vs Flies: The Basics

The word “fly” in its different forms

Before we get into flies or flys, let’s first break down the different forms of the verb “fly.”

1. Fly (base form) – This is the infinitive or root form of the verb. For example: “I want to fly to New York.”
2. Flew (past tense) – This is the past tense of “fly.” For example: “She flew to Paris last week.”
3. Flown (past participle) – This is the past participle of “fly,” often used with auxiliary verbs. For example: “We have flown to many countries.”
4. Flying (present participle) – This is the form of “fly” used with progressive tenses. For example: “The bird is flying in the sky.”

So, when do we use “flies” and “flys”?

Here’s the first big takeaway:

• “Flies” is the correct plural form of fly when referring to multiple insects or creatures that can fly. For example: “The room was filled with flies.”
• “Flys” is actually a common misspelling of flies. The word “fly” doesn’t take an “s” when you’re talking about multiple of the insect or creature. It’s always “flies.”

Scenario Example:

Let’s say you’re emailing a friend and describing a recent trip to a farm. You might write:

“I spent the afternoon on the farm last weekend. There were so many flies buzzing around the barn, it was hard to focus on anything else. I couldn’t believe how many flies there were!”

Notice how we’re referring to multiple insects, and the correct form is flies—not flys.

How Do We Use “Flys” or “Flies” in Different Tenses?

Now that we’ve established the basic difference between flies and flys, let’s dive into how these words behave in different tenses.

Present Tense: “Flies” as a third-person singular verb

When you’re writing in the present tense, flies is used for third-person singular subjects. In simpler terms, if you’re talking about one person, animal, or thing performing the action of flying, you’ll use flies.

• Correct: “The bird flies every morning.”
• Incorrect: “The bird flys every morning.”

Example in an email:

Let’s imagine you’re writing an email to your colleague about a recent team-building event:

“Hey Sarah,
I wanted to give you an update on the event. The drone flies smoothly now, and we’re planning to use it for our upcoming presentations. I’ll send over the footage once it’s ready.
Cheers,
Tom”

In this case, flies refers to the drone’s ability to fly, and we use it because “drone” is a third-person singular noun.

When Should You Use “Flys”?

The form flys is not grammatically correct in standard English. It’s a common mistake that occurs when people assume that adding an “s” to a verb in the present tense applies to all nouns, but this is not the case.

Is it “Flys” or “Flies” in the Past Tense?

When talking about the past, flies remains the plural form of “fly” referring to the insect, but flys should never be used.

For example, in the past tense, we still say:

• Correct: “Yesterday, the flies filled the room.”
• Incorrect: “Yesterday, the flys filled the room.”

Example in an Email:

“Hi John,
I wanted to let you know that the new office setup is fantastic! However, there were some flies around the lunchroom yesterday, which was a little distracting. I think we might need to get a few more fly traps.
Best,
Emily”

Again, flies is the correct choice because you are referring to multiple insects in the past.

Fly vs Flies: The Noun Form

When “fly” is used as a noun, it refers to an insect, and flies is the plural form.

For instance:

• “There are many flies near the food.”
• “A fly landed on my sandwich.”

Example in a Scenario:

Let’s take an everyday situation where you’re writing a brief note to a friend:

“Hey Mike,
I noticed flies around the garbage cans in the alley. Maybe we should call pest control to take care of it.
Talk soon,
Julie”

Here, flies refers to the insects around the garbage, and it’s used in its plural form.

Flys or Flies: In Common Phrases

Some idiomatic expressions also include flies or flys:

• “Time flies” is a common phrase used to say that time passes quickly.
• “Fly by” refers to something happening very quickly, often in relation to time. For example: “The weekend really flies by when you’re having fun.”

Scenario Example in an Email:

“Hey Ben,
I can’t believe how quickly this week has flown by. It feels like it was just Monday, and now we’re already planning for next week’s meeting.
Best,
Sarah”

In this case, flown by (past participle) is used to describe how time has passed quickly.

Flys vs Flies: Common Mistakes to Avoid

1. Confusing the plural form

The most common mistake people make is confusing flys (incorrect) with flies (correct) when talking about more than one insect. Remember, the plural of fly is always flies.

2. Misusing flys in present tense

It’s easy to get confused when conjugating verbs, especially with irregular verbs like fly. However, in the present tense, flies is always used for third-person singular subjects. Flys should never be used in this context.

3. Incorrect past tense forms

In the past tense, fly becomes flew, and flown is used as the past participle. Don’t fall into the trap of writing flys as a past tense form.

4. Using “flys” when talking about insects

If you’re talking about insects, always use flies as the plural form. “Flys” is never correct in this situation.

Summary: Flys or Flies?

In conclusion, flies is the correct term in nearly all scenarios, whether you’re talking about multiple insects or using it as the third-person singular form of the verb fly. Flys is almost always a misspelling.

Here’s a quick recap of when to use flies or flys:

Usage	Correct Form	Example
Plural of fly (insects)	flies	“There are too many flies in the kitchen.”
Third-person singular (verb)	flies	“The bird flies over the trees.”
Past tense (insects or action)	flies	“Yesterday, the flies were all over the food.”
Idiomatic expression	flies	“The day flies by when you’re busy.”

Final Thoughts on “Flys or Flies”

Whether you’re drafting an email, writing an article, or chatting with a friend, always remember that flies is the grammatically correct form to use in nearly every case. By avoiding the temptation to write flys, you’ll improve both your grammar and your communication skills.

So, next time you wonder, is it flys or flies?, you’ll know the right answer: it’s flies—every time!