The category of voice is a system of two-member oppositions of the type asks – is asked, asking – being asked, to ask – to be asked, has asked – has been asked, etc. which show the direction of the action towards the participants of the action.

To establish the category of voice we use the opposition: ― active – passive+.

The category of voice is closely connected with lexical classification of verbs into transitive / intransitive . The general rule is: only transitive verbs have two forms: active and passive. But English is peculiar in this respect – even intransitive verbs can be used in passive constructions. --- : to live, to sleep, to lie, to sit. e. g. They live in this house. The house is lived in. The fact that intransitive verbs in passive forms may become transitive can explain why passive constructions are so widely used.

The problem arises in connection with the possibility of double use of some verbs in English.

e.g. I opened the door. The door opened.

There are three approaches here. One can treat the verb to open as two different verbs: in the first case the verb to open is transitive, in the second – intransitive. According to another approach we deal with the same verb but standing in different voice forms. In the latter example it is called the middle voice. B.A. Ilyish claims that opened in both cases is the form of the active voice.

The construction to be + Part 2 is not always passive.

Cf. e. g. The window was broken by my brother yesterday The window was broken and dirty. In the first case the verb expresses an action, in the second – a state (qua­lity) of things. In the first case the meaning of the construction is passive, in the second – active.

It expresses a passive action when:

1) the grammatical form is continuous, perfect or future;

2) the verb is durative;

3) different adverbial modifiers are employed or the doer of the action is expressed.

But there is a point of view (L.S. Barkhudarov, D.A. Shteling, G.N. Vorontsova) according to which the construction to be + Part 2 should always be treated as a passive construction, since Participle 2 is a verbal form, and both: the meaning of an action and the meaning of a state are inherent to the lexical meaning of the verb.

There are attempts to treat constructions V + self-pronoun as the reflexive voice forms, the pronoun being the auxiliary element. To decide whether it is true one must answer the question: is the reflexive pronoun in He hurt himself  a direct object, and thus, a separate part of the sentence or is it part of the predicate? It seems there is no direct answer to this question. In cases like He hurt himself it is quite possible to treat the pronoun as a word used to build up a form of voice in the verb. But in cases like He found himself …the pronoun is obviously not an auxiliary word.

Another problem arises when we try to analyze constructions like to greet each other, to praise one another , etc. The problem is whether these combinations belong to forms of the reciprocal verbal voice . The grounds to admit the existence of the reciprocal voice are very weak as sentences like They helped each other and their child, in which a pronoun functions as an object to the verb, are rare in the language. Besides, there are sentences like They kissed which have the reciprocal meaning and correspond to They kissed each other. Their form, however, does not allow to say they are different from the active voice forms.

Some linguists insist on regarding the constructions to get + Part 2, to become + Part 2 as passive constructions, analytical grammatical forms. But in this case the language acquires several passive voices. Cf. He was married. He got married. He became married.

It is obvious that there is some difference in meaning in to get + Part 2 and to become + Part 2. Both retain their lexical meaning. Besides, one and the same Participle 2 married cannot have three passives at a time. So, combinations with different link-verbs should not be treated as analytical grammatical passive forms.