Demonstrative Pronouns

   The words this, that, those, that, so, the same, one, when used alone are Demonstrative Pronouns; when used with nouns, they are adjectives (So can not be used as an adjective).
This (or that) is my house. Such (=what was suggested) was not my object. What I mean is this.
These are called Demonstrative Pronouns as they point out some objects to which they refer. Some examples and their uses are given below:

   This and these refer to something that is near to the speaker in position, time or thought; that and those denoting something being more distant.
This house is ours, not that.
   When two nouns have been mentioned before, this refers to the latter, and that refers to the former.
Reading and playing are both necessary; this gives us enjoyment, that gives knowledge.
Dogs are more faithful than cats; these attach themselves to places, and those to persons.
   They are often used for preceding nouns and clauses.
This book is better than that of Jadu. I have read English, and that (I have read) at WBSU. He went there and this (=the fact that he went there) proves his courage.

   Such as a Demonstrative Pronoun stands for a noun or phrase; it may be used for either number.
If you are my friend, show yourself as such.

   The same is a Demonstrative Pronoun in such fields as, I will do the same as you (=that which you do).
   The use of 'the same' for 'it' in such sentences as "He filed a petition, I have gone through the same," is now restricted only to legal documents.

   So is a Demonstrative Pronoun after say, think, tell, etc.
I said or think so (=this or that).
In "We walked a mile or so (=about the distance)." so is an Indefinite Demonstrative.

   One and its plural Ones are Demonstrative Pronouns when they stand for preceding nouns.
The oranges are not ripe, please send me some ripe ones (=oranges).