Der Pilot, der das Flugzeug fliegt, ist international bekannt.

The pilot who flies the airplane is internationally known.

Breakdown of Der Pilot, der das Flugzeug fliegt, ist international bekannt.

• sein: to be
• der Pilot: the pilot
• der: who
• das Flugzeug: the airplane
• fliegen: to fly
• international: international
• bekannt: known

Questions & Answers about Der Pilot, der das Flugzeug fliegt, ist international bekannt.

Why are there two ders in the sentence?

The first der is the definite article for Pilot (masculine singular nominative). The second der is the relative pronoun linking Pilot to the clause der das Flugzeug fliegt.

Why is the relative pronoun der and not den or dem?

Relative pronouns agree in gender, number, and case with their antecedent. Pilot is masculine singular and the clause is in the nominative (because it describes “who” is doing the flying), so the correct form is der.

Why is das Flugzeug in the accusative case?

In the relative clause der das Flugzeug fliegt, the verb fliegen is used transitively (“to fly something”), making das Flugzeug the direct object—hence accusative.

Why does fliegt appear at the end of the relative clause?

German subordinate clauses (including relative clauses) follow a verb‑final word order. Every element except the conjunction or relative pronoun comes before the finite verb, which goes to the end.

Why is there a comma before the second der?

German grammar requires a comma before any subordinate clause—including relative clauses—to separate it clearly from the main clause.

Why are international and bekannt not inflected?

Here bekannt is used predicatively after the linking verb ist, so it remains uninflected. International functions as an adverb modifying bekannt, so it also does not take adjective endings.

Could I replace der Pilot, der das Flugzeug fliegt with der Pilot, welcher das Flugzeug fliegt?

Yes, welcher is a valid relative pronoun, though it’s somewhat more formal or bookish. Most native speakers simply use der in everyday language.

Can the sentence be shortened by omitting the relative clause?

Absolutely. If you don’t need the extra detail about flying the plane, say:
Der Pilot ist international bekannt.

What’s another way to express “flies the airplane” in German?

You can use steuern (“to steer/navigate”) instead of fliegen if you prefer:
Der Pilot, der das Flugzeug steuert, ist international bekannt.