INTRODUCTORY IT

What is introductory it?

When the subject is an infinitive phrase, the sentence often begins with it. Instead of saying ‘To find fault with others is easy’,  we say, ‘It is easy to find fault with others’. More examples are given below :


When the subject is a clause
When the subject is a clause, the sentence usually begins with it. So instead of saying ‘That he was once a communist is true’, we say, ‘It is true that he was once a communist’.

Example: 
It does not matter whether he comes or not (Whether he comes or not does not matter)
It is required that he should pay the fine (That he should pay the fine is required)
It is clear that he overheard our conversation (That he overheard our conversation is clear)

Introductory it with seem, appear and look
Introductory it is also used with seem, appear and look when the subject is an infinitive phrase, a phrase with a gerund in it or a clause.

Example:
It looked doubtful whether she would come

It seemed strange that she should behave like that.

It seems possible that she may quit the job.


Introductory it as an object
It is sometimes used as the object of the verbs think, feel, deem, count, consider etc.
Example:
Don’t you think it dangerous to drive so carelessly?
I consider it a privilege to have this opportunity of welcoming you.
I think it odd that she doesn’t write to me these days.

Introductory it in questions
The introductory it is sometimes used in questions.


Example:
Who was it that broke the window?
Why was it that he stole the bread?