Learn Hardcore German: Der Gast staunt über das moderne Museum.

German staunen is a prepositional verb (eine Präpositionalverb). It never takes a bare accusative object like “staunt das Museum”; instead, it always appears as staunen über + Accusative to express “to marvel at” or “to be amazed by.”

How do I know that das moderne Museum is in the accusative case and not the nominative?

Because it’s the object of the preposition über, which in this verb construction demands the accusative. Note that neuter singular nominative and accusative both use das Museum, so you must look at the role in the sentence (object of über) to identify the case.

Why does the adjective modern take the ending -e in moderne rather than -es or another ending?

After a definite article (das) German employs the weak adjective declension. In the neuter singular nominative and accusative, the weak ending is -e (hence das moderne Museum). If you had an indefinite article (ein), you would see the strong ending: ein modernes Museum.

Could I replace das moderne Museum with a pronoun to avoid repetition, and if so, how?

Yes. Because das moderne Museum is part of a über + accusative construction, you use a pronominal adverb:

Darüber: Der Gast staunt darüber.
You cannot say “staunt es” here; you need darüber whenever you replace an object of über.

What’s the perfect tense of this sentence?

Use haben + past participle of staunen:

Der Gast hat über das moderne Museum gestaunt.
In German perfect tense, regular verbs form the past participle with ge-…-t, so staunen becomes gestaunt.

Why is the verb staunt ending in -t?

In the present tense for third-person singular (er/sie/es), regular weak verbs add -t to the stem. The stem of staunen is staun-, so you get er staunt.

Can I change the word order, for example by placing Über das moderne Museum at the beginning of the sentence?

Yes. German main clauses require the finite verb in second position. If you prepose the prepositional phrase, you get:

Über das moderne Museum staunt der Gast.
The verb staunt stays in second position, and the subject follows the verb.

What’s the difference between staunen über and bewundern?

Both can describe being impressed, but:

staunen über focuses on amazement or wonder (“to marvel at, be astonished by”).
bewundern is “to admire” in a more appreciative, praise-oriented sense.
So Der Gast staunt über das moderne Museum means the guest is amazed by its modernity, while Der Gast bewundert das moderne Museum suggests he admires or praises it.

Why does the sentence use Der Gast (definite article) instead of Ein Gast (indefinite article)?

Using Der Gast indicates a specific, known guest (definite). Ein Gast would introduce “a guest” (indefinite) into the conversation. Both are grammatically correct, but they change the nuance:

Ein Gast staunt … = “A guest is amazed …” (unspecified guest)
Der Gast staunt … = “The guest is amazed …” (a particular guest you have in mind)