Difference between This and It in English Grammar
‘This’ is used as a demonstrative pronoun in English grammar whereas ‘it’ is a personal pronoun. There are some subtle differences between the usage of ‘this’ and ‘it’. For instance,
This is my book.
This looks good on you.
In both of these sentences, ‘this’ signifies and refer to as a relation to book, color, dress or a piece of jewelry that may be used in the conversation prior to the mentioned sentence.
The word ‘it is used in the third person form as a personal pronoun. For example:
He looked at it with awe.
He signaled it to keep quiet.
Here, the word ‘it’ has been used as the third person indicative of an animal such as a dog. It can be used to express exclamation. Sample this, “How wonderful it is!”
The usage of these words should be precise and accurate.