Demonstrative pronouns

Study the following sentences.

• This is a gift from my brother.
• Both watches are good; but this is better than that.
• My views are in accordance with those of the Chairman.
• These are mere excuses.
• That is the Red Fort.
• Mumbai mangoes are better than those of Bangalore.

You will have noticed that the pronouns in bold text are used to point out the objects to which they refer. They are, therefore, called demonstrative pronouns. There are four demonstrative pronouns in English: this, that, these and those.
Note that this and that are used with singular nouns. These and those are used with plural nouns.
This and these refer to object/objects close at hand. That and those refer to what is ‘over there’.

• This is better than that.

Demonstrative adjectives
This, that, these and those are demonstrative adjectives when they are used with nouns.

• That book is mine.
• What is that noise?
• These flowers are very beautiful.
• Those days were the best.
• This horse is faster than that horse.

Special uses
That and those are often used to avoid the repetition of a preceding noun.

• The streets of Mumbai are busier than those of Paris. (= The streets of Mumbai are busier than the streets of Paris.)

Here the demonstrative those is used to avoid the repetition of ‘the streets’.

Read more: http://www.englishgrammar.org/demonstrative-pronouns/#ixzz2EBEPhCvv