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stuff
vs
thing(s)

Stuff as a noun "stuff" can be used to describe any articles, material, or even activity.

For example: "He is so messy, he has left all his stuff lying around."

"I've got so much stuff to do, I'll never finish it all!"

As a verb "to stuff" means to fill something tightly.

For example: "We stuffed the chicken with sage and onion stuffing."

Thing can be used to refer to anything you don't want to, or can't give a specific name to.

For example "Where is that wooden thing I was using?"

The plural of thing is things.

For example: "They say those things will do all the work in the future, but I think I'll be retired by then."

Stuff can be things and things can be stuff, but stuff is uncountable, whereas things are countable. If you have so many things that you can't count them all, and you have to stuff them all into cupboards and boxes, you probably have too much stuff.

Things vs stuff
Cartoon by Michael Leunig © 
Republished here with permission. 

 

!Note - It's a lot ruder in the UK to tell someone to "get stuffed", than it is in the US or Australia, and they might hit you.

"We are such stuff
As dreams are made on" Shakespeare