time flies so fast 是人们最常用的表达方式。
"Time flies so fast" 是常用俗语，这里的“Time”是一般性的时间概念，指特定时间或某个活动。 "Time fly so fast" 只能用于部分情境下。
Time flies so fast; it feels like just yesterday we were in middle school, and now I’m a bridesmaid at your wedding.
Time flies so fast when you’re having fun.
Time flies so fast when you have a baby. You have to make sure to soak up every moment you have with them because they grow up so quickly.
It’s weird how time flies so fast when you’re on vacation but drags on when you’re working.
I had no idea that you got married already—time flies so fast!
I was surprised to learn that time flies so fast as you get older.
Time flies so fast when I’m with my boyfriend.
I’ve been so busy, and it seems like time flies so fast when you’ve got stuff going on.
My vacation abroad taught me that time flies so fast when you’re doing something you enjoy.
**Time flies so fast **as an adult that it’s difficult to make time to do everything you want to do.
It makes me sad that time flies so fast; I wish I could slow it down so I could enjoy happy moments more.
Have you ever seen time fly so fast as when you are having a good time with old friends?
I have never noticed how time can fly so fast.
They said they had never felt time fly so fast as they did when they were spending time in the cabin on the lake.
How can time fly so fast as it is this year? It's already December!
He asked himself, "How did time fly so fast and leave me behind to suffer in loneliness?"
Time can fly so fast that you are already remembering something as a memory that you were just planning seemingly a few days before.