Introductory It

When the subjective is an infinitive phrase

We begin a sentence with it when the real subject is an infinitive phrase. So instead of saying, ‘To accept your advice is difficult’, we say, ‘It is difficult to accept your advice’.

Structure: It + verb + subject complement + infinitive phrase (real subject)

It is easy to learn English. (= To learn English is easy.) It is easy to find fault with others. (= To find fault with others is easy.)

Note that when we wish to emphasize the infinitive phrase, it may be put at the beginning, especially when it is short.

To err is human. (OR It is human to err.) To become a well known writer was his life-long ambition. (OR It was his lifelong ambition to become a well known writer.) To invest all your money in shares is foolish. (OR It is foolish to invest all your money in shares.)

When the subject is a gerund phrase

When the real subject is a phrase that includes a gerund, it is used as a provisional subject to begin the sentence. So instead of saying ‘Your trying to fool us is no good’, we say, ‘It is no good your trying to fool us.’

It won’t be any good complaining to the manager. (Complaining to the manager won’t be any good.) It is silly throwing away this opportunity. (Throwing away this opportunity is silly.) Will it be any good my talking to him about it? (Will my talking to him about it be any good?) It is no fun having so many children to look after. (Having so many children to look after is no fun.)

Note that it is possible to change the gerund into an infinitive.

It won’t be any good for me to complain to the manager. It is silly (for you) to throw away this opportunity. Will it be any good for me to talk to him about it? Many of these sentences can also be re-written as exclamatory sentences. How silly of you to throw away this opportunity!

Introductory It – Part II

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’.

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.

It looked doubtful whether she would come It seemed strange that she should behave like that. It appeared unwise to offend him. It does not seem much good going on with the work.

Introductory it as an object

It is sometimes used as the object of the verbs think, feel, deem, count, consider etc.

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.

Who was it that broke the window? It is Peter who broke the window. Why was it that he stole the bread?

Classifications of predicate

Like subjects, there are three types of predicates:- 1). Simple predicate - a complete verb (a verb and any helping verbs)  stand was dancing could have sung is sleeping  2). Complete predicate - a simple predicate plus all modifiers  sit on the couch was singing sweetly could have danced across the floor was reading loudly  3). Compound predicate – two or more predicates with the same subject was singing quietly and sweetly

Classes of predicate

Carlson classes

After the work of Greg N. Carlson, predicates have been divided into the following sub-classes, which roughly pertain to how a predicate relates to its subject:

Stage-level predicates

A stage-level predicate ("s-l predicate" for short) is true of a temporal stage of its subject. For example, if John is "hungry", that typically lasts a certain amount of time, and not his entire lifespan.

S-l predicates can occur in a wide range of grammatical constructions and is probably the most versatile kind of predicate.

Individual-level predicates

An individual-level predicate ("i-l predicate") is true throughout the existence of an individual. For example, if John is "smart", this is a property of him, regardless which particular point in time we consider.

I-l predicates are more restricted than s-l ones. I-l predicates can't occur in presentational "there" sentences (a star in front of a sentence indicates that it is odd or ill-formed):

There are police available. ("available" is s-l)

*There are firemen altruistic. ("altruistic" is i-l)

S-l predicates allow modification by manner adverbs and other adverbial modifiers. I-l ones do not.

John spoke French loudly in the corridor. ("speak French" can be interpreted as s-l)

*John knew French loudly in the corridor. ("know French" can't be interpreted as s-l)

When an i-l predicate occurs in past tense, it gives rise to what is called a "lifetime effect": The subject must be assumed to be dead or otherwise gone out of existence.

John was available. (s-l  no lifetime effect)

John was altruistic. (i-l lifetime effect.)