Der Bericht muss sorgfältig geprüft worden sein.

The report must have been carefully checked.

Breakdown of Der Bericht muss sorgfältig geprüft worden sein.

• müssen: must
• sorgfältig: carefully
• der Bericht: the report
• geprüft worden sein: to have been checked

Questions & Answers about Der Bericht muss sorgfältig geprüft worden sein.

Why are geprüft, worden and sein all at the end of the sentence?

In German, when you have a present‐tense modal verb (muss) combined with a perfect passive, you create a verb cluster at the clause end. It consists of:

1. geprüft (the past participle of prüfen)
2. worden (the past participle of werden, used to form the passive)
3. sein (the infinitive auxiliary you need for the perfect tense)
   This stacking of participles and infinitives is the normal word‐order rule for a perfect passive with a modal.

Why is worden used, and not geworden?

There are two past participles of werden in German:

• geworden is used when werden means “to become.”
• worden is the special past participle used only in passive‐voice constructions.
  In a perfect passive you must use worden, not geworden.

What role does sein play at the end?

In a normal perfect tense (active or passive), German uses haben or sein as an auxiliary. For the perfect passive you would say:
“Der Bericht ist sorgfältig geprüft worden.”
When you add a modal in front, you shift sein out of its finite form into an infinitive. Hence it appears at the very end.

How do you form a perfect passive when there is a modal verb?

The pattern is:

• put the modal in its finite form (here muss)
• turn the perfect passive auxiliaries into infinitives (i.e. worden, sein)
• keep the past participle of the main verb (here geprüft) just before them
  Result: muss ... geprüft worden sein

Could I instead say Der Bericht muss sorgfältig geprüft werden?

Yes—but that is the present passive (“The report must be carefully checked”) and doesn’t imply the checking is already completed. The perfect passive (geprüft worden sein) stresses that the action has to have taken place.

How would I turn it into a yes/no question?

Invert muss and the subject, then keep the verb cluster at the end:
“Muss der Bericht sorgfältig geprüft worden sein?”

Where do I place nicht if I want to say “The report must not have been carefully checked”?

You place nicht before the adverbial or the verb cluster:
“Der Bericht muss nicht sorgfältig geprüft worden sein.”
This construction negates the whole necessity‐plus‐completion idea.