Question

Flowers from Africa are now grown in Middle Eastern greenhouses and sold to markets in Europe and Asia.

Answer 1

Flowers from Africa are now grown in Middle Eastern greenhouses and sold to markets in Europe and Asia

Middle Easter is a proper adjective for noun ”greenhouses.”

A proper adjective is actually a proper noun which is placed before a noun, where an adjective should be, in order to modify and describe it.

Proper adjectives take proper nouns and shift their function to fill the role of an adjective, or a word that's modifying another noun.

Proper nouns are those nouns refering to specific people, places, or things.

Answer 2

Flowers from Africa are now grown in Middle Eastern greenhouses and sold to markets in Europe and Asia

is a proper adjective for noun ”greenhouses”