✅ "Piece" is a countable noun because you can count individual units of it (one piece, two pieces) and it has a plural form (pieces).

❌ "Information" is an uncountable noun, referring to an abstract concept that cannot be counted individually. You cannot say "two informations."

❌ "Knowledge" is an uncountable noun, representing an abstract concept that cannot be pluralized or counted directly. You wouldn't say "three knowledges."

❌ "Furniture" is an uncountable noun, referring to a collection of items rather than individual pieces. You cannot say "four furnitures," but rather "four pieces of furniture."