Is this sentence gramatically correct or incorrect In dem Haus Friedrich tanzt?

The sentence "In dem Haus Friedrich tanzt?" is grammatically incorrect in German.

Here's why:

* Word order: In German, the verb typically comes at the end of the sentence in a question.

* Case: "Friedrich" needs to be in the nominative case because it is the subject of the sentence.

Here's a corrected version:

Tanzt Friedrich in dem Haus?

This sentence is grammatically correct because:

* The verb "tanzt" is at the end of the sentence.

* "Friedrich" is in the nominative case.