Demonstrative adjectives in English are words used before a noun to indicate which specific item or items the speaker means. They point to things as near or far and as singular or plural. The main demonstrative adjectives in English are this, that, these, and those. The choice depends on both distance and number. They always come directly before the noun they modify.

Rule
Use a demonstrative adjective before a noun to identify which item you mean.
Choose this or these for items that are near.
Choose that or those for items that are farther away.
Use this and that with singular nouns, and use these and those with plural nouns.

This is the demonstrative adjective for one thing that is near the speaker. That is the demonstrative adjective for one thing that is farther from the speaker. Both are singular, so they are used with singular countable nouns. In standard use, they do not change form based on gender or case.

Word/Phrase	Definition
this	This is the word for one noun that is near the speaker.
that	That is the word for one noun that is farther from the speaker.

These is the demonstrative adjective for more than one thing that is near the speaker. Those is the demonstrative adjective for more than one thing that is farther from the speaker. Both are plural, so they are used with plural countable nouns. They remain the same regardless of the nouns’ gender.

Word/Phrase	Definition
these	These is the word for plural nouns that are near the speaker.
those	Those is the word for plural nouns that are farther from the speaker.

Demonstrative adjectives must match the number of the noun they modify. Use this with a singular noun and these with a plural noun. Use that with a singular noun and those with a plural noun. Agreement is based on whether the noun is singular or plural, not on meaning or intention.

Rule
Use this with a singular noun.
Use these with a plural noun.
Use that with a singular noun.
Use those with a plural noun.

In English, near usually means close to the speaker, often within reach or within the immediate area. Farther can mean physically farther away, out of reach, or outside the immediate context. Speakers may also use that and those for things not present, such as items being discussed or remembered. The choice is about psychological or conversational distance as well as physical distance.

Rule
Use this and these for items in your immediate area or attention.
Use that and those for items outside your immediate area or attention.
Speakers can use that and those for things not present but being mentioned.

In standard English, the demonstrative adjective comes directly before the noun it modifies. If there are other adjectives, the typical order is demonstrative, then other adjectives, then the noun. The demonstrative does not replace the article because it already specifies the noun. This pattern applies in both statements and questions.

Rule
Place the demonstrative adjective immediately before the noun.
If there are other adjectives, put the demonstrative first.
Do not use an article with a demonstrative adjective.