THIS-THAT-THESE-THOSE

DEMONSTRATIVES -
THIS-THAT-THESE-THOSE.

This/that/these/those show the relative distance between the speaker and a noun.

This/That

Examples:
This dog is mine.
This is mine.
That dog is hers.
That is hers.

These/ Those

Examples:
These babies have been smiling for a while.
These are mine.
Those babies in the nursery have been crying for hours.
Those are yours.