THIS/THAT/THESE/THOSE

THIS & THAT

This and That are for singular nouns.

This is used for an object which are near to use

     example: This is my pen in my hand.

That is used for an an object which is not near to us.

     example: That is my bag you are carrying.

THESE & THOSE

These and Those are for plural nouns.

These are used for objects which are near to use.

     example: These are my new shoes I'm wearing.

Those are used for objects which are not near to use.

     example: Those were my co-workers at the meeting.