werden plus Partizip II
The passive puts the event first and the doer in the background. The object of the active sentence becomes the subject, and the doer usually disappears. You see this a lot in notices, instructions and announcements.
Active and passive
Der Architekt baut das Haus.
The architect is building the house.
Active: the doer is the subject.
Das Haus wird gebaut.
The house is being built.
Passive: no doer.
Mein Fahrrad wird gerade repariert.
My bike is being repaired right now.
Wir werden morgen informiert.
We'll be informed tomorrow.
Die Zimmer werden jeden Tag geputzt.
The rooms are cleaned every day.
Ich werde am Flughafen abgeholt.
I'm being picked up at the airport.
From active to passive
The Akkusativ object of the active sentence becomes the Nominativ subject of the passive sentence. You can see it with masculine nouns: den Wagen becomes der Wagen.
Die Firma schickt die Rechnung heute.
The company is sending the invoice today.
Die Rechnung wird heute geschickt.
The invoice is being sent today.
Naming the doer: von or durch
Most passive sentences don't name the doer. If you do want to name it, English uses by. German has two words.
von + Dativ: a person or an institution
Der Patient wird von der Ärztin untersucht.
The patient is being examined by the doctor.
Die Straße wird von der Stadt saniert.
The road is being resurfaced by the city.
durch + Akkusativ: a cause or a means
Das Dach wird durch den Sturm beschädigt.
The roof is being damaged by the storm.
Viele Unfälle werden durch Müdigkeit verursacht.
Many accidents are caused by tiredness.
Passive without a subject
If the active sentence has no Akkusativ object, there is nothing to turn into a subject. A Dativ object stays in the Dativ, and the verb is always singular: Mir wird geholfen. A verb with no object at all gives a general statement about an activity: Hier wird nicht geraucht. If another word is in first position, you don't need es.
Mir wird geholfen.
I'm being helped.
Hier wird nicht geraucht.
No smoking here.
Sonntags wird nicht gearbeitet.
No work is done on Sundays.
Heute Abend wird getanzt!
There's dancing tonight!
