Der internationale Zug fährt pünktlich.

The international train runs on time.

Breakdown of Der internationale Zug fährt pünktlich.

• der Zug: the train
• pünktlich: on time
• international: international
• fahren: to run

Questions & Answers about Der internationale Zug fährt pünktlich.

Why is Der used instead of Ein at the beginning?

Der is the definite article for masculine singular nouns in the nominative case. We use Der because we’re talking about a specific train (“the international train”). If we wanted to say “an international train” (nonspecific), we would use Ein and adjust the adjective accordingly: Ein internationaler Zug fährt pünktlich.

Why does internationale end with ‑e instead of ‑er?

German adjectives take different endings depending on the article and case (this is called adjective declension). After the definite article der in the nominative masculine singular, adjectives use the weak ending ‑e. Hence der internationale Zug. With ein, you’d get the strong ending ‑er: ein internationaler Zug.

Why is Zug capitalized but internationale and pünktlich are not?

In German, all nouns are capitalized—Zug (train) is a noun. Adjectives (internationale) and adverbs (pünktlich) remain lowercase.

Why is the verb fährt in the second position and not at the end of the sentence?

German main clauses follow the verb‑second (V2) rule: the finite verb must occupy the second position. Here the subject phrase (Der internationale Zug) is first, so the verb fährt comes immediately after.

What part of speech is pünktlich here, and why doesn’t it change form?

In this sentence, pünktlich functions as an adverb modifying the verb fährt (“runs on time”). Adverbs in German are invariable—they do not take case, gender, or number endings.

Could we put pünktlich at the very beginning of the sentence? What would change?

Yes. If you front pünktlich, it occupies the first position and you still follow V2, so fährt remains second:
Pünktlich fährt der internationale Zug.
This word order shifts emphasis onto the punctuality of the train.

Can we use the indefinite article ein here? How does that affect the adjective ending?

Absolutely. With ein (nominative masculine singular), the adjective must take the strong ending ‑er:
Ein internationaler Zug fährt pünktlich.
The sentence still means “An international train runs on time,” but now it’s nonspecific.