Funciones garamaticales

Grammatical Function: Mood.
The Mood shows the attitude of the speaker or the writer to the action or state described by the verb.
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* Indicative mood
* Imperative mood
* Subjunctive mood
* Conditional mood
* Generic mood
* Negative mood
* Interrogative mood
* Optative mood
* Admirative mood
* Cohortative mood
* Jussive mood
*Potential mood

The Indicative Mood.
The Indicative Mood is used in factual statements. All intentions in speaking that a particular language does not put into another mood use the indicative. It is the most commonly used mood and is found in all languages. Ex:
Paul is reading books.
The Imperative Mood. 
The Imperative Mood expresses commands, direct requests, and prohibitions.In many circumstances, directly using the imperative mood seems blunt or even rude, so it is often used with care. Ex: Paul, read that book.
The Subjunctive Mood.
The Subjunctive Mood has several uses in independent clauses. Examples include discussing hypothetical or unlikely events, expressing opinions or emotions, or making polite requests. A subjunctive mood exists in English, butappears to be falling out of common use; many native English speakers do not use it. Ex: I suggested that Paul read books.
Paul is not in fact reading the book. Contrast this with the sentence "Paul reads books", where the verb read has the third person singular ending.
The Conditional Mood.
The Conditional Mood is used to express a lack of certainty about whether the action ever occurs,particularly, but not exclusively, in conditional clauses. In English, the conditional is manifested by means of the modal auxiliary 'would' added to the bare infinitive. Ex: I would buy.
Typically, it introduces subordinate clauses which are headed by a phrase roughly meaning 'on the condition that', such as 'if', 'as long as', etc., and these phrases can have their meaning intensified by itemslike 'even', as in 'even if'. Ex: I would buy a house if I earned a lot of money.
 (I might buy a house, if I earn a lot of money, but I do not and thus earning a lot of money is a condition for buying a house.)
The Generic Mood.
The Generic Mood is used to make generalizations about a particular class of things, e.g. in "Rabbits are fast", one is speaking about rabbits in general, ratherthan about particular fast rabbits. English has no means of morphologically distinguishing generic mood from indicative mood, however the distinction can easily be understood in context by surrounding words.
Compare, for example: rabbits are fast, versus, the rabbits are fast. Use of the word "the" implies specific, particular rabbits, whereas omitting the word "the" implies the genericmood simply by default.
The Negative Mood.
The negative mood expresses a negated action. In many languages, this is not distinct mood; negativity is expressed by adding a particle before, after, or both. Standard English brings in a helper verb, do usually, and then adds “not” after it: "I did not go there".
In Indo-European languages, it is not customary to speak of a negative mood, since inthese languages negation is originally a grammatical particle that can be applied to a verb in any of these moods. In some non-Indo-European languages, the negative mood counts as a separate mood, an example of which is Japanese, which conjugates verbs in the negative after the suffix -nai (indicating negation) has been added, e.g. tabeta (ate) and tabenakatta (did not eat).

The InterrogativeMood.
In interrogative sentences, the subject is typically after the verb (if there's only one verb) or between the auxiliary and main verbs. But sometimes the order is subject + verb:
* You did what?!
These sentences would be regarded as examples of the 'interrogative mood':
* When was the last time we met?
* Do you want tea or coffee?
Interrogative sentences express...