Question inversion in English like in German?

There are two distinct processes affecting word order in questions:

1. Subject-verb inversion. This shows up in yes-no questions, but only auxiliary verbs are typically inverted in modern English, so a form of “do” is added with non-auxiliaries (part of a phenomenon called “do-support”). Is the appointment at 9:30? is a yes-no question with subject-verb inversion.

2. Wh-fronting. Interrogative words like what, when, whom, how come at the front of their clause, even if their grammatical role is something that would normally come in a different position (like the object or complement of the verb). So we put when at the start of When is the appointment? even though an answer will use a word order like The appointment is at 9:30.

A typical non-embedded question has both wh-fronting and subject verb inversion (How are you doing?) unless the subject is a wh-word (Who is at the door?).

An embedded question shows wh-fronting, but usually does not show subject verb inversion: I asked them how they were doing or I want to know when the appointment is. Inversion (I asked them how were they doing, I want to know when is the appointment) is sometimes an acceptable alternative in some dialects, but as a rule, inversion is not preferred in this context in formal English. However, using a comma before the inverted clause often increases the acceptability in standard written English: “I want to know, when is the appointment?”