Question

I never know which of those words to use with and when. Thank you for explanation.

Answer 1

"Those" is when we speak of something in the distance, for an example: "Those books", like they're a few feet away.
We use "these" when the books are really close to us, or when we hold the books.
Remember to always use "those" and "these" with plural nouns.

Answer 2

Determiners                                                         Pronouns

I might get myself a pair of those shoes.             You can use any one of these computers.

I need to paint those windows.                             Can I have one of these?

 

These and those are plural. We use them as determiners and pronouns and furtherly, to point to people and things.

Taken from Cambridge Dictionary,British Grammar.

Answer 3

those , as in those over there

 

these , as in these right here

Answer 4

similar..THIS and THAT  this is closer, that is farther away

this these.     that those.   these is plural of this.   those is plural of that