Wir fragen, warum der Topgriff fehlt.

Because warum der Topgriff fehlt is a subordinate clause.

In German, subordinate clauses are normally separated from the main clause by a comma:

• Wir fragen, warum der Topgriff fehlt.

The main clause is:

• Wir fragen

And the subordinate clause is:

• warum der Topgriff fehlt

This comma is required in standard German.

Because warum introduces a subordinate clause, and in German subordinate clauses the conjugated verb usually goes to the end.

So:

• main clause: Wir fragen
• subordinate clause: warum der Topgriff fehlt

Compare:

• Der Topgriff fehlt.
  In a main clause, the verb is in the usual second-position pattern.
• ..., warum der Topgriff fehlt.
  In a subordinate clause, the verb moves to the end.

This is one of the most important word-order patterns in German.

Because der Topgriff is the subject of the subordinate clause.

In warum der Topgriff fehlt, the thing doing the fehlen is der Topgriff. In other words, the top handle is missing.

So it must be in the nominative case:

• der Topgriff = nominative masculine

If it were accusative, it would be den Topgriff, but that would not fit here.

Here, fragen takes a clause as its object: warum der Topgriff fehlt.

German fragen can be used in a few common ways:

• jemanden fragen = to ask someone
  
  • Ich frage ihn.
• etwas fragen = to ask something
  
  • Ich frage das. (less common in everyday speech)
• einen Nebensatz fragen = to ask why / whether / when, etc.
  
  • Wir fragen, warum ...
  • Sie fragt, ob ...

So in your sentence, the object is not a noun in a visible case form, but a whole subordinate clause.

Because fragen and nach etwas fragen are related but not identical patterns.

• etwas / einen Nebensatz fragen = to ask a question
• nach etwas fragen = to ask for something / ask about something

Examples:

• Wir fragen, warum der Topgriff fehlt.
  We ask why the top handle is missing.
• Wir fragen nach dem Topgriff.
  We ask about the top handle / ask for the top handle.

In your sentence, the speakers are asking why something is missing, so a warum clause is the natural structure.

Fehlen means to be missing or to be absent.

A very important point: in German, the thing that is missing is the grammatical subject.

• Der Topgriff fehlt. = The top handle is missing.

English speakers sometimes expect a structure more like we are missing the top handle, but German often uses fehlen differently.

Compare:

• Der Schlüssel fehlt. = The key is missing.
• Mir fehlt das Geld. = I am lacking the money / I don’t have the money.

So in your sentence, der Topgriff is the thing that is missing.

Because German often forms compound nouns by combining words into a single noun.

So:

• Top + Griff = Topgriff

This is very normal in German. English often uses separate words where German prefers one compound word.

Also, like all German nouns, Topgriff is capitalized.

Because this is a normal main clause, and German main clauses typically place the finite verb in second position.

Here the structure is:

• Wir = first element
• fragen = finite verb in second position

So:

• Wir fragen, warum der Topgriff fehlt.

German does not always have to begin with the subject, but when something else comes first, the verb still stays in second position:

• Heute fragen wir, warum der Topgriff fehlt.

So wir is first here simply because it is the chosen first element of the main clause.

Yes, and it changes the nuance a bit.

• Wir fragen, warum der Topgriff fehlt.
  We ask why the top handle is missing.
  This can suggest asking someone, raising the question, or investigating it.

• Wir fragen uns, warum der Topgriff fehlt.
  We ask ourselves why the top handle is missing.
  This often means we wonder why.

So both are possible, but uns adds the idea of wondering or asking internally rather than directly asking another person.

Yes. All three can mean why:

• warum
• wieso
• weshalb

Examples:

• Wir fragen, warum der Topgriff fehlt.
• Wir fragen, wieso der Topgriff fehlt.
• Wir fragen, weshalb der Topgriff fehlt.

In many contexts, warum is the most neutral and common choice. The others are also correct, with only small differences in tone or style.

Yes, but the original version is the most straightforward.

For example, you could say:

• Warum der Topgriff fehlt, fragen wir.

This is grammatically possible, but it sounds more marked or literary because the subordinate clause is placed first.

When a subordinate clause comes first, it counts as the first element of the sentence, and the main-clause verb still comes next:

• Warum der Topgriff fehlt, fragen wir.

That is the same verb-second rule again.

In ordinary conversation, Wir fragen, warum der Topgriff fehlt is usually the more natural wording.