Breakdown of Der Zahnarzt hat diesen Zahn sofort ziehen müssen.
haben
to have
dieser
this / that (fem.: diese, neut.: dieses)
müssen
to have to, must
sofort
immediately
Questions & Answers about Der Zahnarzt hat diesen Zahn sofort ziehen müssen.
Why does this sentence end with müssen instead of the past participle gemusst?
Because of the double infinitive rule. When a modal verb like müssen is used alongside another verb (ziehen) in the Perfekt tense, it drops its normal past participle form (gemusst). Instead, it stays in its infinitive form (müssen), sitting right after the main verb's infinitive.
What is the rule for the word order of the two infinitives?
The main action verb (ziehen) comes first, and the modal verb (müssen) goes at the very end. The conjugated helper verb (hat) stays in the standard second position of the sentence.
Is it common to use the Perfekt tense for modal verbs like this?
While grammatically correct, Germans usually prefer the Präteritum (simple past) tense for modal verbs, even in spoken language. A native speaker would more likely say Der Zahnarzt musste diesen Zahn sofort ziehen. However, knowing the double infinitive is essential because you will still encounter it in writing and more complex sentences.
Why is it diesen Zahn and not dieser Zahn?
Zahn is a masculine noun (der Zahn). Since the tooth is the direct object that the dentist is pulling, it takes the accusative case. The demonstrative pronoun dieser (this) changes to diesen for masculine accusative nouns.