One meaning, four more ways to say it
The werden-passive is correct, but in everyday German it is often too heavy. Four constructions say the same thing more lightly: the doer stays out of the sentence, and there is no werden + Partizip II.
The same message, five ways
Das Problem kann gelöst werden.
The problem can be solved.
the werden-passive
Man kann das Problem lösen.
You can solve the problem.
spoken, neutral
Das Problem lässt sich lösen.
The problem can be solved.
spoken and written
Das Problem ist zu lösen.
The problem can be solved.
notices, instructions, reviews
Das Problem ist lösbar.
The problem is solvable.
a property of the problem
man
man is the plainest way out: a normal active sentence with a subject that means nobody in particular. Translate it with you, people or one, or with an English passive: Hier spricht man Deutsch is German is spoken here.
Hier spricht man Deutsch.
German is spoken here.
Hier darf man nicht parken.
You can't park here.
Wie schreibt man das?
How do you spell that?
sich lassen + Infinitiv
With a reflexive sich, lassen means can be done. The thing that would be the subject of the passive is the subject here, too. lassen is the conjugated verb in second position, and the infinitive closes the sentence. A word like gut, leicht, schwer, kaum or nicht usually says how easy it is.
From können + passive to sich lassen
Das Fenster lässt sich nicht öffnen.
The window won't open.
Der Fleck lässt sich kaum entfernen.
The stain will hardly come out.
Das lässt sich machen.
That can be arranged.
a set phrase
sein + zu + Infinitiv
Here too the subject is the thing acted on, and the sentence quietly adds a modal meaning: must or can. Context decides. With a separable verb, zu goes between prefix and verb: auszufüllen.
Two readings
must be done
A bare sentence in a notice, a form or a set of rules is an instruction.
Das Formular ist vollständig auszufüllen.
The form must be filled in completely.
Die Türen sind geschlossen zu halten.
The doors are to be kept closed.
can be done
With leicht, gut, kaum or nichts the sentence judges what is possible, much like sich lassen.
Der Text ist leicht zu verstehen.
The text is easy to understand.
Von draußen war nichts zu hören.
Nothing could be heard from outside.
Adjectives in -bar
This one is word-building: verb stem + -bar gives an adjective meaning able to be verbed, like English -able. It needs a verb with an object, and not every verb has one.
Verb stem + bar
Common -bar adjectives
A -bar adjective describes a property, not an event: Der Akku ist austauschbar says what kind of battery it is, Der Akku lässt sich austauschen says how to do it. In front of a noun it takes the usual adjective endings.
Seine Handschrift ist kaum lesbar.
His handwriting is barely legible.
Der Bezug ist waschbar, bei 40 Grad.
The cover is washable, at 40 degrees.
Bezahlbarer Wohnraum wird knapp.
Affordable housing is getting scarce.
