English Grammar: Verb and Subjunctive

English Grammar: Verb

There are actually four forms of Verb in English: do - to do, did, done, doing.

Base Form = do
Infinitive = to do
Preterit = did
Participle
    Present = doing
    Past = done
Gerund = doing

Usage:
Noun
Modifier: Adjective, Adverb

Infinitive: N, M.
Participle: M.
Gerund: N.

Tense:

	Simple	Progressive
Present	do	am/is/are doing
Past	did	was/were doing
Present Perfect	have done	have been doing
Past Perfect	had done	had been doing
Future	will do	will be doing
Future Perfect	will have done	will have been doing
Condition
Modal

Modal verbs(frequently):
might, may,
could, can, be able to,
should, ought to, be supposed to, had better,
would, will, would rather,
must, do

Mood: Indicative Mood, Imperative mood, Subjunctive Mood.
Subjunctive:

	Subordinate Clause	Main Clause
Present	did	would do
Past	had done	would have done
Modal	should	could, might, should

For example:
If I were a bird, I would fly in the sky.
If she had been a bird, she would have flew away.

Vice: Passive = be done.