The passive voice

In German, the passive voice is a widely used structure. There are two forms of the passive voice. The first consists of a conjugation of the verb werden and a past participle:

werden + past participle

Es wird + gebrochen.

It is (being) broken.

The active voice

But before looking at the passive voice, let’s consider the active voice, which is essentially the parent of the passive voice. The active voice sentence is made up of a subject, a 
transitive verb, and a direct object, a combination of direct and indirect objects, or the object of a dative verb:
subject + transitive verb + object → active voice
Er hat den Richter gestört.               He disturbed the judge.
Sie gibt dem Herrn ein Geschenk.  She gives the man a gift.
Wir haben der Lehrerin gedankt.   We thanked the teacher.
The passive voice in German

The elements of the passive voice sentence are the conjugation of werden and a past participle. Let’s look at the various tenses of the passive voice in the third person singular with the verb lesen:

Present:                       wird gelesen                 is read

Past:                              wurde gelesen              was read

Present perfect:       ist gelesen worden      has been read

Past perfect:              war gelesen worden    had been read

Future:                         wird gelesen werden   will be read

   Notice that the perfect tenses use worden as the past participle of werden. This only occurs in the passive voice, in which werden is translated as to be. When werden means to become or get, its past participle is geworden.

  If the active voice sentence has an accusative direct object, the passive voice sentence uses the direct object as its subject, which must be in the nominative case. The tense of the verb in the active sentence becomes the tense of the verb werden in the passive sentence.   The active voice subject becomes the object of the preposition von in the passive sentence. And the verb in the active sentence is formed as a past participle in the passive sentence. For example:

Er stört den Richter.                                            He disturbs the judge.

Passive subject:                                                der Richter

Passive form of werden in the present    wird

tense:

Passive object of von:                                      von ihm

Passive past participle:                                 gestört

The passive voice version of the sentence:

Der Richter wird von ihm gestört.                    The judge is disturbed by him.

If the active sentence were in the past tense, the passive sentence would become:

Der Richter wurde von ihm gestört.                 The judge was disturbed by him.

If it were in the present perfect tense, the passive sentence would become:

Der Richter ist von ihm gestört worden.         The judge has been disturbed by him.

And if it were in the future tense, the passive sentence would become:

Der Richter wird von ihm gestört werden.     The judge will be disturbed by him.

  If an active sentence has both a direct object (accusative case) and an indirect object (dative case), it is only the direct object that can become the subject of the passive form of the active sentence.

  The indirect object remains in the dative case. However, the indirect object can be placed

at the beginning of the sentence or it can follow the conjugated verb:

subject + werden + indirect object + past participle → passive sentence

or

indirect object + werden + subject + past participle → passive sentence

For example:
Active voice:     Tina hat ihm das Buch gegeben.    Tina gave him the book.
Passive voice:   Das Buch ist ihm von Tina              The book was given to him by Tina.
                                gegeben worden.
                                or Ihm ist das Buch von Tina                       
                                gegeben worden.
Active voice:     Wir schickten einem Freund We sent a friend a gift.
                                ein Geschenk.
Passive voice:  Ein Geschenk wurde einem A gift was sent to a friend by us.
                                Freund von uns geschickt.
                                or Einem Freund wurde ein
                                Geschenk von uns geschickt.
Dative objects in the passive voice

When the object of a dative verb in an active sentence is placed in a passive voice sentence, the object must remain in the dative case. The subject of the passive sentence will be the optional pronoun es, thus conjugating werden with a third person singular subject:

dative object + werden + (es) + past participle → passive sentence

For example:
Active voice:       Man glaubt ihm nicht.                     People don’t believe him.
Passive voice:    Ihm wird nicht geglaubt.                 He isn’t believed.
                                      (Es wird ihm nicht geglaubt.)
Active voice:      Martin hat dem Mann gedankt.     Martin thanked the man.
Passive voice:   Dem Mann ist von Martin                The man was thanked by Martin.
                                 gedankt worden.
As with other passive voice sentences, the tense of werden in the passive sentence must be the tense of the verb in the active sentence, and that verb becomes a past participle in the passive voice sentence. If the verb glauben is in the past tense, the passive sentence becomes:
Ihm wurde nicht geglaubt.            He wasn’t believed.If glauben is in the present perfect tense, the passive sentence becomes:
Ihm ist nicht geglaubt worden.    He wasn’t (hasn’t been) believed.
If glauben is in the future tense, the passive sentence becomes:
Ihm wird nicht geglaubt werden. He won’t be believed.

If the subject of an active sentence is man (one, you) or another word that does not specify

anyone in particular (they, people, some, and so on), that word can be omitted from the 
passive voice sentence:
Active—  Man glaubte ihm nicht.
Passive—Ihm wurde nicht geglaubt.
In a passive sentence, the preposition of is translated into German by either von or durch.

Von is used most often when the “agent” of the action of the verb is a person, but also occurs when the agent is a natural cause or force of nature. Durch is used primarily with actions caused by a thing but also with actions caused by a person who acts as an intermediary. For example:

Person:                Der Roman wurde von Sabine          The novel was read by Sabine.
                                    gelesen.
Natural cause:  Das Dorf wird von einem                   The village is threatened by a forest
                                 Waldbrand bedroht. fire.
Thing:                   Die Epidemie ist durch Bakterien    The epidemic was caused by
                                    verursacht worden.                             bacteria.
Intermediary:  Die Familie wird durch einen            The family is informed by a police
                                    Polizisten benachrichtigt.                  officer.
Modal auxiliaries
  Modal auxiliaries are most commonly used together with another verb in infinitive form: er
kann singen (he can sing); er muss singen (he must sing). Modals are used in the same way with a “passive infinitive.” A passive infinitive is composed of a past participle followed by the infinitive werden: besucht werden (to be visited); gesehen werden (to be seen).

  When writing sentences with a modal auxiliary and an infinitive or passive infinitive, it is

the modal auxiliary that is conjugated. That means that in the perfect tenses, the auxiliary will be haben and not sein, since all modal auxiliaries require haben as their auxiliary. First let’s look at a passive sentence that is introduced by a variety of modal auxiliaries:

modal + participle + werden
Es kann + nicht veröffentlicht + werden.
It can’t be published.
modal + participle + werden
Es muss + nicht veröffentlicht + werden.
It doesn’t have to be published.
modal + participle + werden
Es soll + nicht veröffentlicht + werden.
It should not be published.
Now consider these examples of a passive sentence with a modal auxiliary in the various
tenses:
Es kann nicht gemacht werden.                It can’t be done.
Es konnte nicht gemacht werden.             It couldn’t be done.
Es hat nicht gemacht werden können.     It couldn’t be done.
Es wird nicht gemacht werden können.   It won’t be able to be done.

Notice that in the present perfect and the future tenses, just like with a single infinitive, a passive infinitive forms a double infinitive structure with the modal auxiliary:

gemacht werden (passive infinitive) + können (modal infinitive)
→ gemacht werden können
Another passive form
As mentioned earlier, there is a second type of passive. It consists of a conjugation of the verb sein and a past participle. This second passive offers the past participle as an adjective. The difference between werden in the passive and sein in the passive is perhaps more clearly illustrated in English.
Consider the following pair of sentences in the present tense:
The old clock is being repaired.
The old clock is repaired.
The first sentence shows an action that is in progress. The second sentence describes the clock as already being in a state of repair—it is adjectival in nature. In German, the difference is marked by the use of the two different auxiliaries:
Die alte Uhr wird repariert.
Die alte Uhr ist repariert.

If the participle in the two example sentences above is replaced with a true adjective, only the second sentence, with sein, will make sense without changing its meaning. The sentence with werden, on the other hand, would lose its passive meaning, werden reverts to its meaning of to become or get, and the sentence may not make complete sense. Compare the following two sentences, using the true adjective unbezahlbar, with the previous examples using the participle repariert:

Die alte Uhr wird unbezahlbar.     The old clock becomes priceless.

Die alte Uhr ist unbezahlbar.         The old clock is priceless.

werden + past participle → passive sentence
sein + past participle acting as adjective → adjective