Demonstrative Determiners
Demonstrative Determiners are used to indicate things or people in relationship to the speaker or writer in space or time.
This, that, these, those are the Demonstrative Determiners in English.
This and these indicate nearness to the speaker, as in –
This is a beautiful drawing.
These chocolates are for you.
That and those indicate distance from the speaker, as in –
That girl is very smart.
Those flowers, over there, are beautiful.
This and that are used before singular countable and uncountable nouns, e.g.
This pen is expensive. (Countable noun)
This water is dirty. (Uncountable noun)
That boy is handsome. (Countable noun)
That rice is good. (Uncountable noun)
These is plural of this.
Those is plural of that.