TYPES OF ADJECTIVES
Most adjectives do not change form whether the noun it describes is singular or plural. For example we say big tree and big trees, old house and old houses, good time and good times. There are, however, some adjectives that do have different singular and plural forms. The common words this and that have the plural forms these and those. These words are called demonstrative adjectives because demonstrate or point out what is being referred to.
Another common type of adjective is the possessive adjective which shows possession or ownership. The words my dog or my dogs indicate that the dog or dogs belong to me. I would use the plural form our if the dog or dogs belonged to me and other people. The chart below shows the forms of possessive adjectives.
*Person is used here as a grammar word and has these meanings:
1st person or the self (I, me, we),
2nd person or the person spoken to (you)
3rd person or the person spoken about (he, she, him, her, they, them).