Ich weiß genau, wann der Zug kommt.

I know exactly when the train comes.

Breakdown of Ich weiß genau, wann der Zug kommt.

• kommen: to come
• ich: I
• der Zug: the train
• wissen: to know
• wann: when
• genau: exactly

Questions & Answers about Ich weiß genau, wann der Zug kommt.

Why is it weiß and not kenne? In English we just say “I know.”

German distinguishes two verbs for “to know”:

• wissen – knowing a fact, information, answer to a question
  
  • Ich weiß, wann der Zug kommt. = I know when the train comes.
• kennen – being familiar with a person, place, thing, or situation
  
  • Ich kenne den Zug. = I am familiar with / I know that train.
  • Ich kenne Berlin gut. = I know Berlin well.

Here, you know a fact (the time when the train comes), so you must use wissen → ich weiß.
Ich kenne genau, wann der Zug kommt is wrong in standard German.

Why is there a comma before wann?

In German, a comma is mandatory before a subordinate clause.

• Ich weiß genau, → main clause
• wann der Zug kommt. → subordinate clause (introduced by wann)

So the comma is not optional style — German spelling rules require it: > Main clause , subordinate clause

Why does the verb go to the end in wann der Zug kommt?

In German:

• In a main clause, the finite verb goes in position 2:
  
  • Ich weiß genau. (I know exactly.)
• In a subordinate clause, introduced by a subordinating conjunction (like wann, dass, weil, wenn, obwohl), the finite verb goes to the end:
  
  • … wann der Zug kommt.
  • … dass der Zug pünktlich kommt.
  • … weil der Zug Verspätung hat.

So wann der Zug kommt has the verb kommt at the end because it’s a subordinate clause introduced by wann.

Ich weiß genau, wann kommt der Zug is wrong in German; that word order is only for a direct question:

• Wann kommt der Zug? (direct question) ✔
• Ich weiß, wann der Zug kommt. (indirect question) ✔

Why is it der Zug and not den Zug or dem Zug?

German articles change with case. The forms for masculine singular are:

• Nominative: der Zug (subject)
• Accusative: den Zug (direct object)
• Dative: dem Zug (indirect object)

In the clause wann der Zug kommt:

• The verb is kommt (“comes”).
• The thing that comes is the train → that means the train is the subject.
• The subject in masculine singular takes nominative = der.

So: der Zug (not den Zug / dem Zug) because it’s the subject of kommt.

Why is kommt in the present tense if we mean a future event (when the train will come)?

German often uses the present tense for scheduled future events, especially with timetables and fixed plans:

• Der Zug kommt um 8 Uhr. = The train arrives at 8 o’clock.
• Morgen arbeite ich nicht. = I’m not working tomorrow.

So:

• Ich weiß genau, wann der Zug kommt.
  can mean:
  • I know exactly when the train comes (in general / regularly), or
  • I know exactly when the train will come (in this particular case).

You could theoretically say …wann der Zug kommen wird, but in normal speech this sounds heavy and is usually unnecessary.

What’s the difference between wann, wenn, and als? Why do we use wann here?

Very briefly:

• wann – means “when?” as a question word, used in:

  • direct questions: Wann kommt der Zug?
  • indirect questions: Ich weiß, wann der Zug kommt.

• wenn – means “whenever / if / when (repeated or general condition)”:

  • Wenn der Zug kommt, gehe ich zum Bahnsteig.
    = Whenever / If the train comes, I go to the platform.

• als – means “when” for a single event in the past:

  • Als der Zug kam, war ich schon da.
    = When the train came, I was already there.

In Ich weiß genau, wann der Zug kommt, you are “answering” a when-question inside the sentence, so you must use wann, not wenn or als.

Ich weiß genau, wenn der Zug kommt is incorrect in standard German for this meaning.

Can genau go somewhere else? For example: Ich weiß, wann genau der Zug kommt?

Yes, genau (exactly) is flexible. All of these are grammatical, with slightly different emphasis:

1. Ich weiß genau, wann der Zug kommt.

   • Neutral, very natural. genau modifies weiß (“I know exactly”).

2. Ich weiß, wann genau der Zug kommt.

   • Focus is more on the time, as in “I know exactly when the train comes (not just roughly).”

3. Ich weiß ganz genau, wann der Zug kommt.

   • Stronger: “I know exactly / very precisely when the train comes.”

You normally wouldn’t put genau at the very end:

• Ich weiß, wann der Zug kommt genau ❌ (sounds wrong/foreign).

Can I leave out genau? Does it change the meaning a lot?

Yes, you can omit it:

• Ich weiß, wann der Zug kommt. = I know when the train comes.
• Ich weiß genau, wann der Zug kommt. = I know exactly when the train comes.

Without genau, you’re just saying you know the time.
With genau, you stress that you know it precisely (to the exact minute, not just “around 5-ish”).

Is there a difference between kommt and ankommt here? Could I say wann der Zug ankommt?

Yes, you can say:

• Ich weiß genau, wann der Zug ankommt.

The nuance:

• kommt – literally “comes”; in the context of trains, it usually means “arrives” anyway.
• ankommt – explicitly “arrives”.

In everyday speech about trains, kommt is very common and normally understood as “arrives”, especially with a time:

• Der Zug kommt um 8 Uhr. = The train arrives at 8.

Using ankommt just makes the “arrival” meaning more explicit, but both are fine.

How would I say “I don’t know exactly when the train comes” in German?

You negate the verb wissen in the main clause and keep the structure of the subordinate clause:

• Ich weiß nicht genau, wann der Zug kommt.

Word order:

• Ich (subject)
• weiß (verb, position 2)
• nicht genau (negation + adverb)
• , wann der Zug kommt. (subordinate clause)

You could also say:

• Ich weiß genau nicht, wann der Zug kommt. – possible, but less natural; usually nicht goes before genau here: nicht genau.

Why is Zug capitalized?

In German, all nouns are capitalized, no matter where they appear in the sentence.

• der Zug (train) – noun → capitalized.
• ich, wann, kommt – pronoun, conjunction, verb → lower case.

So Zug must be written with a capital Z:

• Ich weiß genau, wann der Zug kommt. ✔
• Ich weiß genau, wann der zug kommt. ❌

What is that ß in weiß? Can I write weiss?

The letter ß is called “Eszett” or “scharfes S”.

• In weiß, it represents a sharp “s” sound after a long vowel (wei- is long).
• In Switzerland and Liechtenstein, ß is not used; they write weiss instead.

In Germany and Austria, the standard spelling is:

• weiß – correct, standard
• weiss – understood, but officially a spelling mistake in those countries

Pronunciation is the same in both spellings: like English “vice” but with v pronounced [v] instead of English [v/f mix].