The sentence "time flies when you have fun" is correct and usable in written English. You can use it whenever you want to express the idea that fun and happy times pass quickly. For example, you could write: "I can't believe how quickly our vacation was over! Time flies when you have fun!".
Time flies when you have fun!
People say time flies when you are having fun and I have had the best 15 years of my life.
"They say that time flies when you're having fun, well, results happen much faster when you're having fun, too".
You may have heard that time flies when you're having fun, and there's some research to indicate that our perceptions of time really do quicken when we're enjoying ourselves.[7].
Have fun, because it is a well known fact that time flies when you're having fun.
(Unless that's what you're waiting to get) the saying, "Time flies when you're having fun," wasn't made up just for fun, you know.
We've all heard that "time flies when you're having fun".
When I feel like I can't trust my brain 100%, Ludwig really comes in handy. It makes me translate and proofread faster and my output more reliable.
Claudia Letizia
Head Translator and Proofreader @ organictranslations.eu