No, the adjective 'unusual' is a common adjective. A proper adjective is an adjective derived from a proper noun, for example Swiss cheese or Victorian architecture.
Vietnamese is the proper adjective for Vietnam.
Since spice isn't a proper noun, it can't have a proper adjective. The adjective of spice is spicy.
Ghanian is the proper adjective for Ghana.
Since writer is not a proper noun, it doesn't have a proper adjective.
Hawaiian is the proper adjective for Hawaii.
"Unusual" is an adjective.
There is no verb "unusual" is an adjective.
The word unusual *is* an adjective, the negative of the adjective usual.A related adjective that has a different meaning is unused, the negative of the past participle used.
No. Unusual is an adjective, something that describes a noun.
Adjective
The proper adjective for southwest is "southwestern."
The proper adjective is Haitian.
The proper adjective for Portuguese is "Portuguese."
Vietnamese is the proper adjective for Vietnam.
No, old is not a proper adjective. A proper adjective is an adjective derived from a proper noun, such as Swiss cheese, Bolivian pottery, Chinese silk, etc.
The proper adjective for George is Georgian.
The proper adjective for Siam is Siamese.