Wir müssen den Fahrplan überprüfen.

We have to check the timetable.

Breakdown of Wir müssen den Fahrplan überprüfen.

• wir: we
• müssen: must
• überprüfen: to check
• der Fahrplan: the timetable

Questions & Answers about Wir müssen den Fahrplan überprüfen.

Why does the sentence use den Fahrplan instead of der Fahrplan or dem Fahrplan?

Because Fahrplan is the direct object of überprüfen, so it must be in the accusative case. The masculine nominative der Fahrplan becomes den Fahrplan in accusative. Dem Fahrplan would be dative, which we don’t use here.

How do I know Fahrplan is masculine?

German nouns each have a gender (masculine, feminine, neuter). You learn this either by memorizing or by checking a dictionary or list. Dictionaries list der Fahrplan (masculine).

Why is überprüfen not split into über … prüfen?

German verbs with certain prefixes (be-, emp-, ent-, er-, ge-, miss-, ver-, zer-, and some verbs with über-) are inseparable. überprüfen is inseparable, so the prefix über stays attached in all forms. Only separable prefixes (e.g., auf-, ab-, ein-) split in main clauses.

Why is müssen in second position and überprüfen at the end?

In a main clause with a modal verb, the modal (here müssen) takes the finite-verb (V2) slot, and the main verb (infinitive überprüfen) goes to the very end.

What tense is this sentence, and what nuance does it convey?

It’s present tense (Präsens) of the modal müssen, expressing a current necessity or obligation: “We have to check the timetable.”

When should I use müssen versus sollen?

Use müssen for necessities that arise from circumstances or internal decisions (“We need to…”). Sollen implies an external instruction or recommendation (“We are supposed to…”). Here, Wir müssen den Fahrplan überprüfen suggests it’s really necessary, not just a suggestion.

How would I turn this into the passive voice?

You make Fahrplan the subject and use müssen + past participle + werden:
Der Fahrplan muss überprüft werden.

How do I pronounce überprüfen correctly?

überprüfen is pronounced [ˈyːbɐˌpʁyːfən].

• ü sounds like the [y] in French lune.
• Stress is on the first syllable: ÜBER-prüfen.
• The r in German is a uvular or somewhat rolled sound.