Have you ever wondered whether you should say “time has flown by” or “time has flown by”? These two expressions are often confused because they both come from the irregular verb fly. However, only one is grammatically correct in modern English. In this guide, you’ll learn the differences, grammar rules, practical examples, common mistakes, and simple tips to help you use the correct phrase with confidence.
Comparison Overview
Both “time has flown by” and “time has flown by” are intended to express the idea that time passed very quickly. However, they are not interchangeable. The difference lies in the grammatical form of the verb fly.
- Time has flown by is grammatically incorrect because it uses the simple past tense after the auxiliary verb has.
- Time has flown by is grammatically correct because it uses the past participle, which is required in the present perfect tense.
Quick Comparison Table
| Feature | Time Has Flew By | Time Has Flown By |
| Grammar | ❌ Incorrect | ✅ Correct |
| Verb Form | Simple Past (Flew) | Past Participle (Flown) |
| Present Perfect | No | Yes |
| Formal Writing | No | Yes |
| Everyday Conversation | Sometimes heard (incorrectly) | Common and Correct |
| Recommended Usage | Never | Always |
Definition of Time Has Flew By
“Time has flown by” is an incorrect English phrase.
It combines has, which requires a past participle, with flew, which is the simple past tense of the verb fly.
Although many English learners and even native speakers occasionally say it, the phrase is considered grammatically incorrect.
Incorrect examples:
- ❌ Time has flew by so quickly.
- ❌ The summer has flew by.
- ❌ My vacation has flew by.
The correct replacement is always:
- ✅ Time has flown by.
Definition of Time Has Flown By
“Time has flown by” is the correct expression in English.
It means that time has passed very quickly.
The phrase uses the present perfect tense, formed with:
Subject + has/have + past participle
Since flown is the past participle of fly, the phrase is grammatically correct.
Examples:
- Time has flown by since we graduated.
- This year has flown by.
- The holidays have flown by.
- My childhood has flown by.
- The weekend has flown by.
Main Differences Between Time Has Flew By and Time Has Flown By
| Point | Time Has Flew By | Time Has Flown By |
| Correct English | ❌ No | ✅ Yes |
| Uses Past Participle | No | Yes |
| Uses Simple Past | Yes | No |
| Suitable for Exams | No | Yes |
| Suitable for Professional Writing | No | Yes |
| Recommended in Everyday English | No | Yes |
Key Difference
The only difference is the verb form.
- Flew = Simple Past
- Flown = Past Participle
Since has always requires the past participle, only flown is correct.
Understanding the Verb “Fly”
The confusion becomes much easier when you know the forms of the irregular verb fly.
| Verb Form | Word |
| Base Form | Fly |
| Third Person | Flies |
| Present Participle | Flying |
| Simple Past | Flew |
| Past Participle | Flown |
Examples:
- Birds fly every day.
- The bird flew away yesterday.
- The bird has flown away.
Notice that has is always followed by flown, never flew.
Grammar Guide
The verb fly is an irregular verb, meaning its past tense and past participle do not follow the regular -ed pattern.
Verb Forms
| Tense | Example |
| Present | fly |
| Past | flew |
| Past Participle | flown |
Present Perfect Structure
Subject + has/have + past participle
Examples:
- She has written a letter.
- They have gone home.
- Time has flown by.
Never write:
- ❌ Time has flew by.
How Each Term Is Used in Sentences
Time Has Flew By
This expression should not be used because it is grammatically incorrect.
Incorrect examples:
- ❌ Time has flew by.
- ❌ Summer has flew by.
- ❌ My childhood has flew by.
- ❌ The semester has flew by.
- ❌ The weekend has flown by.
Time Has Flown By
Correct examples:
- Time has flown by since our last meeting.
- This month has flown by.
- The school year has flown by.
- Life has flown by faster than expected.
- The evening has flown by.
Common Mistakes Learners Make
Many learners make the following mistakes:
- Using flew after has.
- Forgetting that fly is an irregular verb.
- Confusing simple past with present perfect.
- Thinking and flying are interchangeable.
- Writing incorrect sentences in essays and emails.
Simple Rules to Remember
Remember these easy rules:
- Has + Flown ✅
- Have + Flown ✅
- Had + Flown ✅
- Has + Flew ❌
- Have + Flew ❌
Memory trick:
Fly → Flew → Flown
Think:
Yesterday = Flew
Has/Have/Had = Flown
Quick Tips for Writing and Speaking
- Always check irregular verbs before writing.
- After has, always use the past participle.
- If you’re unsure, remember fly → flew → flown.
- Read your sentence aloud.
- Avoid using has flew in formal writing.
When to Use Each One
Use “Time Has Flown By”
Use this phrase whenever you want to express that time has passed quickly.
Examples include:
- Talking about childhood.
- Remembering vacations.
- Reflecting on school years.
- Discussing work experience.
- Looking back on relationships.
Examples:
- Time has flown by since graduation.
- The weekend has flown by.
- This semester has flown by.
- Our friendship has flown by so quickly.
- The last decade has flown by.
Use “Time Has Flew By”
There are no correct situations in modern standard English where this phrase should be used.
Always replace it with:
Time has flown by.
When NOT to Use Each One
Do Not Use “Time Has Flew By”
Avoid this phrase:
- In school assignments.
- During English exams.
- In professional emails.
- In academic papers.
- In books.
- In business communication.
Do Not Use “Time Has Flown By”
While this phrase is correct, don’t use it when the sentence requires the simple past tense.
Correct:
- The bird flew over the lake yesterday.
Incorrect:
- ❌ The bird flew yesterday.
Because yesterday requires the simple past.
Which One to Use (Decision Guide)
Follow this simple guide.
| Your Sentence Contains | Correct Choice |
| Has | Flown |
| Have | Flown |
| Had | Flown |
| Yesterday | Flew |
| Last Week | Flew |
| Last Year | Flew |
| Present Perfect | Flown |
| Simple Past | Flew |
Easy Decision Tree
Does your sentence contain “has,” “have,” or “had”?
- Yes → Use Flown
- No → Check whether the sentence needs the simple past (Flew).
Real-World Practical Examples
Time Has Flew By Examples (Incorrect Usage)
The following examples are incorrect and are shown only to illustrate common mistakes.
- Education: ❌ Time has flown by during my first semester.
- Daily Life: ❌ The weekend has flown by.
- Business: ❌ The project has flown by quickly.
- Technology: ❌ The last decade of technology has flown by.
- Conversation: ❌ Wow, time has flown by since we met.
Correct each sentence by replacing flew with flown.
Time Has Flown By Examples
- Education: Time has flown by since I started college.
- Daily Life: The weekend has flown by so quickly.
- Business: The first quarter has flown by faster than expected.
- Technology: Twenty years of technological progress have flown by.
- Writing: Time has flown by while working on this novel.
- Science: Research time has flown by during the experiment.
- Conversation: Wow, time has flown by since our last reunion!
- Travel: Our vacation has flown by.
- Family: The kids have grown up because time has flown by.
- Work: My first year at this company has flown by.
Self-Assessment (Fill in the Blanks)
- I will use ______ when referring to the present perfect tense. The correct word is ______ because it follows has.
- I will use ______ after have. The correct word is ______ because have requires the past participle.
- I will use ______ in the sentence “Time has ______ by.” The correct word is ______ because fly is irregular.
- I will use ______ after had. The correct word is ______ because it is the past participle.
- I will use ______ in formal writing. The correct word is ______ because it follows standard grammar.
- I will use ______ after has. The correct word is ______ because flew cannot follow has.
- I will use ______ when talking about years passing quickly. The correct word is ______ because it forms the present perfect.
- I will use ______ in a professional email. The correct word is ______ because it is grammatically correct.
- I will use ______ when describing my vacation. The correct word is ______ because the action connects to the present.
- I will use ______ in an English exam. The correct word is ______ because it is the accepted form.
- I will use ______ when describing an action that happened yesterday. The correct word is ______ because it is the simple past.
- I will use ______ in “The bird ______ over the trees.” The correct word is ______ because it refers to a completed past event.
- I will use ______ in “The bird has ______ away.” The correct word is ______ because it follows has.
- I will use ______ in “The years have ______ by.” The correct word is ______ because it follows have.
- I will use ______ when talking about a completed experience connected to the present. The correct word is ______ because it requires the past participle.
- I will use ______ after has in “The semester has ______ by.” The correct word is ______ because it is grammatically correct.
- I will use ______ in “The airplane ______ over the city yesterday.” The correct word is ______ because it is simple past.
- I will use ______ in “Time has ______ by since graduation.” The correct word is ______ because it uses the present perfect.
- I will use ______ when writing a business report. The correct word is ______ because it is standard English.
- I will use ______ in “Life has ______ by so quickly.” The correct word is ______ because flown is the correct past participle.
Answers
- flown — because it requires the past participle.
- flown — because have requires the past participle.
- flown — because the present perfect uses the past participle.
- flown — because had takes the past participle.
- Time has flown by — because it is grammatically correct.
- flown — because flew cannot follow has.
- Time has flown by — because it expresses the present perfect.
- Time has flown by — because it is the accepted standard form.
- Time has flown by — because it connects a past action to the present.
- Time has flown by — because it is correct English.
- Flew — because yesterday requires the simple past.
- Flew — because it describes a completed past action.
- flown — because it requires the past participle.
- flown — because have requires the past participle.
- flown — because the present perfect uses the past participle.
- flown — because it is the correct verb form after has.
- Flew— because it is the simple past tense.
- flown — because the sentence is in the present perfect tense.
- Time has flown by — because it follows standard grammar.
- flown — because flown is the correct past participle of fly.
When comparing “time has flown by” and “time has flown by,” the correct choice is clear: “time has flown by” is the only grammatically correct expression in standard English. The confusion comes from the irregular verb fly, whose forms are fly – flew – flown. Remember that flew is the simple past tense, while flown is the past participle used after has, have, and had. Whether you’re writing an essay, sending an email, speaking in a meeting, or having a casual conversation, choosing “time has flown by” will make your English sound accurate, natural, and fluent. Keeping the simple rule “Has + Flown, Never Has + Flew” in mind will help you avoid this common mistake every time.
Conclusion
Understanding the difference between “time has flown by” and “time has flown by” is easier once you know how the irregular verb fly works. While both phrases may sound similar, only “time has flown by” is grammatically correct because flown is the past participle used with helping verbs like has, have, and had. In contrast, flew is the simple past tense and should never follow these helping verbs. Whether you’re writing an essay, preparing for an English exam, sending a professional email, or simply improving your everyday communication, choosing the correct phrase helps you sound more fluent and confident. By remembering the simple pattern fly – flew – flown, you can avoid one of the most common grammar mistakes English learners make. With regular practice and careful attention to verb forms, you’ll naturally use “time has flown by” correctly in both speech and writing.
FAQs
Is “time has flown by” grammatically correct?
No, “time has flown by” is grammatically incorrect. The verb flew is the simple past tense of fly, but after has, you must use the past participle flown. The correct expression is “time has flown by,” which follows the rules of the present perfect tense.
Is “time has flown by” the correct expression?
Yes, “time has flown by” is the correct and widely accepted expression in English. It means that time has passed very quickly and uses the proper present perfect structure of has + past participle, making it suitable for both formal and informal communication.
Why do people confuse “flew” and “flown”?
People often confuse these words because fly is an irregular verb. Unlike regular verbs that simply add -ed, irregular verbs change forms. Flew is the simple past tense, while flown is the past participle. Knowing this difference helps prevent common grammar mistakes.
What does “time has flown by” mean?
The phrase “time has flown by” means that time seems to have passed very quickly. It is commonly used when looking back on enjoyable experiences, busy periods, childhood memories, holidays, or important life events that feel as though they ended sooner than expected.
When should I use “flew” instead of “flown”?
Use flew only in the simple past tense when describing a completed action in the past without helping verbs. For example, “The bird flew away yesterday.” Use flown after has, have, or had, such as “The bird has flown away.”
Can I use “time has flown by” in formal writing?
Yes, “time has flown by” is perfectly appropriate for formal writing, academic essays, business communication, and professional emails. It follows standard English grammar and clearly expresses that a period of time has passed quickly.
Is “time has flown by” common in everyday conversation?
Yes, it is a very common expression in everyday English. Native speakers often use it when talking about birthdays, vacations, school years, careers, or relationships to express surprise at how quickly time has passed.
What is the verb pattern for “fly”?
The verb fly follows this irregular pattern: fly – flew – flown. The base form is fly, the simple past tense is flew, and the past participle is flown. Remembering this sequence makes it much easier to use each form correctly.
How can I remember the correct phrase easily?
A simple memory trick is to remember that has, have, and had always require a past participle. Since the past participle of fly is flown, the correct phrase is always “time has flown by,” never “time has flew by.”
Can using the wrong phrase affect my English writing?
Yes, using “time has flown by” can make your writing appear grammatically incorrect, especially in academic or professional settings. Choosing “time has flown by” demonstrates a proper understanding of English verb forms and helps your writing sound more natural, polished, and accurate.
