Q: You have some lint up your sleeve とはどういう意味ですか?
A: It means that you have little pieces of fuzz on your sleeve(the part you put your arm in)


Q: lint と fluff と fuzz はどう違いますか?
A: Lint is fibers from your clothes. Fluff and Fuzz are essentially the same things.


Q: ①コロコロ(lint roller)をかける、
②プチプチ(bubble wrap)を潰す、
I'd appreciate it if you could teach me about above three phrases and word!! は 英語 (アメリカ) で何と言いますか?
A: I see!
Thank you for teaching about them!!
I'd appreciate it!!
Q: lint in your navel は 英語 (アメリカ) で何と言いますか?
A: bellybutton lint


Q: There’s a lint on your shoulder. Do you want me to get rid of it?
A: It is natural, but we don’t use “a” with lint for some reason. I’m not sure why.

So, “there’s lint on your shoulder” or “a piece of lint on your shoulder” would sound more natural.
Q: "I was getting rid the lint off my pants. because of static and the material they wouldn't come off easily. The lint jumped out a lot under sunlight." この表現は自然ですか?
A: "I was getting rid of the lint on my pants but because of static and the material it wouldn't come off easily. The lint showed a lot under sunlight."
Q: You should move this lint brush from right to left to remove lint on your clothing. If you move it in the opposite direction, you will rather put the lint you've removed into your brush, so be careful. この表現は自然ですか?
A: "If you move it in the opposite direction, you will instead return the lint you've picked up to your clothing, so be careful." Something like that, maybe
Q: "you are trying to take lint off? lint of sweater doesn't come off easily. the struggle is real!" この表現は自然ですか?
A: you would say "sweater lint" and not "lint of sweater."