Demonstrative adjectives

The demonstrative adjectives in English are:
this, these (closer by)
that, those (farther away)
Since they are adjectives, they are followed by a noun: this book is mine, these dogs are cute.

In French they are: ce, cet, cette, ces

ce before a masculine singular noun:
         Je voudrais ce livre (I want this/that book)

cet before a masculine singular noun that begins with a vowel of a "mute h."
         Qui est cet homme? (Who is this/that man?)

cette before a feminine signular noun
          Cette fille est ma soeur! (This/that girl is my sister)

ces before all plural nous.
           Ces garçons sont dans la classe. (These/those boys are in the class)
            Ces filles sont ici. (These/those girls are here)

To distinguish between the one closer by (this, these), French adds -ci after the noun. Thus:
      Ce garçon-ci est mon frère (This boy is my brother)
      Ces filles-ci sont petites (These girls are little)

To distinguish between the ones further away (that, those), French adds -là after the noun. Thus:

       Ce garçon-là est mon frère (That boy is my brother)
       Ces filles-là sont petites (Those girls are little)