Is “stuff ” a plural word? [closed]

I'm wondering which one of these expressions is correct?

This stuff or these stuff?


Solution 1:

Stuff is a collective noun — it represents a group of objects. Just as one would say "this group" or "this pile," one would say "this stuff".

Solution 2:

Stuff is an uncountable, uncount, or mass noun so "this stuff" is correct.