The likely word is a proper noun, the country of Vietnam.
No, wall is a common noun, a singular, concrete, common noun. The word wall is a proper noun only when it is part of a proper name or title such as Henry Wall, The Vietnam Memorial Wall, or the Wall Street Journal.
Vietnam is a noun not a pronoun.
An adjective describes a noun. You could potentially describe a person or thing as "Vietnamese".
"Park Avenue" is a proper noun, because it is a place. Proper nouns like this should always be capitalized.
Pencil proper or common noun
proper noun
Exxon is a proper noun
Yes, the word 'Ali' is a proper noun, the name of a person.A proper noun is the name or title of a specific person, place, or thing.A proper noun is always capitalized.
proper noun
Proper noun
The noun 'gulf' is a commonnoun unless it is the name of a specific gulf.In the term 'gulf countries', the noun 'gulf' is used as an adjective (a function called an attributive noun) to describe the common noun 'countries'.A proper noun is the name of a specific person, place, or thing. For example:Kuwait, Qatar, and Bahrain are PesianGulf countries.China and Vietnam are the Gulf of Tonkincountries.