“The day Fred . . . keyboard” in “The day Fred fell asleep at the keyboard was very hot, and he had had too much to drink at lunchtime.”
“banana” (a noun)
“big bananas” (an adjective 'big', and a plural noun)
“a big banana” (an article 'a', an adjective and a singular noun)
“this big banana” (a determiner 'this', an adjective and a singular noun)
“a very big banana” (an article, an adverb 'very', defining an adjective, and a singular noun)
“a very big banana that tastes great” (an article, an adverb defining an adjective, and a singular noun; followed by a relative clause made up of a relative pronoun 'that', a verb 'tastes', and an adjective 'great')