Hello to all teachers here!
What are the uses of infinitive? its forms? its structures?
Are infinitives as a subject, direct object, subjective complement, appositive (what else?) uses or structures or forms?
And are infinitives as a nouns, adjectives and adverbs uses or structures or forms?
I'm really confused about the forms or uses or structures of infinitives...
When do I say structure? when do i say forms? when do i say uses?
Please help me 'coz I'm really confused....
You certainly do seem to be confused!
Although I would think some general grammar tuition website might be the best thing for so general a question as this, to give a simple summary answer: the infinitive is a NONFINTE form of the verb, consisting in the uninflected verbal stem (in most languages the two are distinct, but in English they are formally identical). When referring to a verb, it is most common to do so in the form of a so-called 'to-infinitive' ('to be', 'to go', etc.), the 'to' being etymologically a preposition, but now more commonly considered a kind of particle prefix forming a syntactic unit with the infinitive, and which may or may not be required depending on the foregoing construction (but always obligatory in uses 2-4 below).
As for the uses of the infinitive, they are essentially fourfold:
1. (plain) VERBAL, e.g.
I can swim.
He is going to study French at college.
(The infinitive is a dependent of the preceding VP.)
2. NOMINAL, e.g.
To be able to speak Japanese well has always been her dream.
(The infinitive serves, like a noun, as sentence subject).
3. ADJECTIVAL, e.g.
It was a day to remember.
(The infinitive adjectivally postmodifies NP 'a day'.)
4. ADVERBIAL, e.g.
To be honest, I was disappointed.
(The infinitive functions as an adverbial disjunct, analogous to e.g. 'strangely' or 'unfortunately'.)
I hope that clears things up for you a little!