The valency (in German: Valenz) of the verb describes the ability to be complemented by other constituents, which are named arguments. Besides the type of constituent (subject or object), the valency also determines their number, ranging from zero to four. Many verbs can have a different valency depending on their usage or role. Compare the lists for understanding:

Avalent and intransitive verbs

1. On the one hand, there are avalent verbs, which do not allow a subject or object. For these verbs, the personal pronoun ‘es’ is used as a dummy or pseudo subject in place of the actual one. This group includes the ‘real’ impersonal verbs (mainly weather verbs):
   • regnen (to rain), nieseln (to drizzle), hageln (to hail), donnern (to thunder), etc.
     • „Morgen regnet es.“ (Tomorrow, it is going to rain.)
       • Although this sentence may seem so, it does not include a subject, merely ‘es’ as a pseudo subject.
2. The monovalent verbs require only a subject and cannot bind an object to themselves. This type includes the intransitive verbs:
   • wachsen (to grow), schlafen (to sleep), wehen (to blow), etc.
     • „Die Blume wächst.“ (The flower grows.)
       • 1st constituent (subject) → ‘Die Blume’ (The flower)

Transitive verbs

In addition, there are the following polyvalent action words, which all belong to the transitive verbs:

1. Divalent verbs require two constituents, one of which is a subject and the other one an object, which is usually (but not always) in the accusative case:
   • helfen (to help), sagen (to say), schneiden (to cut), etc.
     • „Sabrina hilft ihrem Bruder.“ (Sabrina helps her brother.)
       • 1st constituent (subject) → ‘Sabrina’
       • 2nd constituent (dative object) → ‘ihrem Bruder’ (her brother)
2. Trivalent verbs can therefore have three constituents in a sentence, which are one subject and two objects:
   • geben (to give), legen (to put), schreiben (to write), etc.
     • „Der Kunde schreibt dem Unternehmen einen Brief.“ (The customer is writing a letter to the company.)
       • 1st constituent (subject) → ‘Der Kunde’ (The customer)
       • 2nd constituent (dative object) → ‘dem Unternehmen’ (to the company)
       • 3rd constituent (accusative object) → ‘einen Brief’ (a letter)
3. Finally, there are also quadrivalent verbs with one subject and three objects. However, this group is limited to just a few verbs:
   • bitten (to ask), schreiben (to write), übersetzen (to translate), etc.
     • „Tilo bittet seine Gäste für das Missgeschick um Entschuldigung.“ (Tilo apologises to his guests for the mishap.)
       • 1st constituent (subject) → ‘Tilo’
       • 2nd constituent (accusative object) → ‘seine Gäste’ (to his guests)
       • 3rd constituent (prepositional object) → ‘für das Missgeschick’ (for the mishap)
       • 4th constituent (prepositional object) → ‘um Entschuldigung’

Note that many verbs can have a variable valency depending on their use. For example, some of them can be monovalent, divalent or even trivalent.

• Some example verbs are:
  • reden (to talk), erzählen (to tell), essen (to eat), singen (to sing), etc.
    • „Sie singt.“ (She is singing.)
      • monovalent
    • „Sie singt ein Lied.“ (She is singing a song.)
      • divalent
    • „Sie singt ihm ein Lied.“ (She is singing him a song.)
      • trivalent
• Note also that ‘monovalent’ does not mean that adverbials are not possible:
  • „Er schläft.“ (He is sleeping.)
    • monovalent
  • „Er schläft im Bett.“ (He is sleeping in his bed.)
    • monovalent with adverbial

These explanations are related to the topic ‘Valency of German verbs (their relation to the constituents of a sentence)’ and could also be interesting:

• The direct object (accusative object)
• The indirect object (dative object)
• The subject in German grammar
• The object in German grammar
• The pseudo subject in grammar