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Breakdown of Die Stadt erweitert das U-Bahn-Netz, um Staus zu verhindern.
die Stadt
the city
um
in order to
der Stau
the traffic jam
verhindern
to prevent
erweitern
to expand
das U-Bahn-Netz
the subway network
Questions & Answers about Die Stadt erweitert das U-Bahn-Netz, um Staus zu verhindern.
What does erweitert mean here and what part of speech is it?
Erweitert is the third-person singular present form of the verb erweitern, which means “to expand” or “to extend.” In this sentence, it tells us what the subject (“Die Stadt”) is doing.
Why is das U-Bahn-Netz in the accusative case?
Erweitern is a transitive verb—it takes a direct object in the accusative. So das U-Bahn-Netz (the subway network) is the thing being expanded, hence accusative.
Why is there a comma before um?
German requires a comma before an um … zu purpose clause. It marks the boundary between the main clause and the infinitive clause of purpose.
How does the um … zu construction work?
This structure expresses purpose and corresponds to “in order to” in English. You form it with:
• um
• zu + infinitive verb
The whole um … zu phrase comes at the end of the sentence.
Why is Staus plural and what case is it in?
Staus is the plural of Stau (“traffic jam”) because the sentence refers to traffic jams in general. In the um … zu clause verhindern takes its object in the accusative, so Staus is accusative plural.
What gender is Stadt, and why does it have the article die?
Stadt is a feminine noun in German. In the nominative singular, the definite article is die.
Why are there hyphens in U-Bahn-Netz?
“U-Bahn” itself is a shortened compound of Untergrundbahn (underground railway). When it combines with Netz (network), hyphens keep the parts clear and readable: U-Bahn-Netz.
Is verhindern the same as vermeiden?
They’re related but not identical:
• verhindern = “to prevent” (stop something from happening)
• vermeiden = “to avoid” (keep away from something)
Here the city actively prevents traffic jams by expanding the network.
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“How do German cases work?”
German has four grammatical cases: nominative (subject), accusative (direct object), dative (indirect object), and genitive (possession). The case determines the form of articles and adjectives. For example, "the dog" is "der Hund" as a subject but "den Hund" as a direct object.
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