"Cheddar is a kind of cheese" can be shortened to "cheddar is a cheese."
Do you use this rule in real life? How common and practical is this usage? Is it the same rule with "I'd like 2 coffees"? So how do I know which uncountable noun can be used with 'a/an' too?
Other examples are:
Maple is a wood. = Maple is a kind of wood.
Spaghetti is a food. = Spaghetti is a kind of food.
Thank you