Grammatical voice

Grammatical voice is a verb-form that indicates the relationship between the subject and the action expressed by the verb.

In English not only can one say I wrote this page, but one can also say This page was written by me. The former sentence is said to be in the active voice and the latter in the passive voice. In other words, they can be summarized as:

Active: A does B
Passive: B is done by A

The subject and the direct object switch places. The direct object ("this page") becomes the subject in the passive sentence.

Some languages (e.g. Sanskrit and Classical Greek) have a so-called "middle voice". An intransitive verb that appears active but expresses a passive action characterizes the English middle voice. For example, in "The casserole cooked in the oven", "cooked" is syntactically active but semantically passive, putting it in the middle voice. Many deponent verbs in Latin are also survivals of the Indo-European middle voice; many of these in turn survive as obligatory reflexive verbs in French or Spanish.

Some languages have even more grammatical voices. For example, in Classic Mongolian there are five voices: active, passive, causative, reciprocal and cooperative.

Some people consider it bad practice to use the passive voice in English, because it obscures the subject. There is a difference in approach between the UK and the USA. In the UK passive voice is commonly used. In the USA people commonly use the active voice. This is especially true regarding formal and business communications.

Of course, there is still one situation where the passive will always be popular in any country. Many people find it far more appealing to write the second of these two sentences:

I made mistakes.
Mistakes were made.

The passive voice is very often found in academic and journalistic writings. The passive voice is also used to avoid "blame". For example, "The bombing was attributed to unknown freedom fighters."