Subordinate Clauses: wenn, ob in German

Overview

After learning weil and dass, the next pair of subordinating conjunctions to master is wenn (when / if) and ob (whether). These are essential at the A2 level for expressing conditions, time-related situations, and indirect yes/no questions. Like all German subordinate clauses, clauses with wenn and ob send the conjugated verb to the end.

Wenn is a versatile word that can mean "when" (referring to time) or "if" (referring to a condition). Context usually makes the meaning clear. "Wenn ich Zeit habe, komme ich" could mean "When I have time, I'll come" or "If I have time, I'll come." For past events that happened once, German uses "als" instead of "wenn" — but for repeated past events or present/future situations, "wenn" is the right choice.

Ob introduces indirect yes/no questions — situations where you are reporting or wondering about a question rather than asking it directly. "Ich weiß nicht, ob er kommt" (I don't know whether he is coming) turns the direct question "Kommt er?" into a subordinate clause.

How It Works

wenn (when / if)

Usage	Example	English
Condition (if)	Wenn ich Zeit habe, komme ich.	If I have time, I'll come.
Time (when/whenever)	Wenn es regnet, bleiben wir hier.	When it rains, we stay here.
Repeated past	Wenn er kam, waren wir froh.	Whenever he came, we were happy.

Important: For a single past event, use als, not wenn:

• Als ich Kind war, ... (When I was a child, ...) — one-time past
• Wenn ich Kind war, ... (Whenever I was a child, ...) — sounds odd

ob (whether)

Ob turns a yes/no question into a subordinate clause:

Direct Question	Indirect with ob
Kommt er morgen?	Ich weiß nicht, ob er morgen kommt.
Hat sie Zeit?	Ich frage mich, ob sie Zeit hat.
Ist das richtig?	Ich bin nicht sicher, ob das richtig ist.

Word order

Like all subordinate clauses, the conjugated verb goes to the end:

• Wenn ich Zeit habe, ...
• ..., ob er morgen kommt.

When the wenn-clause starts the sentence, the main clause verb follows immediately:

• Wenn es regnet, bleiben wir hier.

Examples in Context

German	English	Note
Wenn ich Zeit habe, komme ich.	If I have time, I'll come.	Condition
Ich weiß nicht, ob er kommt.	I don't know whether he is coming.	Indirect question
Wenn es regnet, bleiben wir hier.	If it rains, we stay here.	Condition/time
Frag ihn, ob er mitkommen will.	Ask him whether he wants to come along.	Indirect question
Wenn du müde bist, geh schlafen.	If you're tired, go to sleep.	Advice with condition
Ich bin nicht sicher, ob das stimmt.	I'm not sure whether that's correct.	Uncertainty
Wenn wir Urlaub haben, fahren wir ans Meer.	When we have vacation, we go to the sea.	Habitual time
Weißt du, ob der Laden offen ist?	Do you know whether the store is open?	Polite inquiry
Wenn ich dich sehe, bin ich froh.	When I see you, I'm happy.	Emotion + time
Ich frage mich, ob das eine gute Idee ist.	I wonder whether that's a good idea.	Reflection

Common Mistakes

Using wenn for single past events

• Wrong: Wenn ich gestern ankam, war niemand da.
• Right: Als ich gestern ankam, war niemand da.
• Why: For a specific, one-time event in the past, German uses "als," not "wenn." "Wenn" in the past implies repetition ("whenever").

Forgetting verb-final order in ob-clauses

• Wrong: Ich weiß nicht, ob kommt er.
• Right: Ich weiß nicht, ob er kommt.
• Why: After "ob," the subject comes before the verb, and the verb moves to the final position.

Confusing ob with wenn for conditions

• Wrong: Ich weiß nicht, wenn er kommt. (meaning "whether")
• Right: Ich weiß nicht, ob er kommt.
• Why: "Ob" is for indirect yes/no questions (whether). "Wenn" is for conditions (if) and time (when). They are not interchangeable.

Wrong main clause word order after a wenn-clause

• Wrong: Wenn es regnet, wir bleiben hier.
• Right: Wenn es regnet, bleiben wir hier.
• Why: The wenn-clause fills position 1, so the main clause verb must be in position 2, immediately after the comma.

Usage Notes

The wenn/als distinction is one of the most commonly tested points in German exams. The rule is straightforward: wenn for present, future, and repeated past; als for a single event in the past. A good mnemonic: "als" = "once upon a time" (one time), "wenn" = "whenever" or "if."

In everyday speech, ob appears in many polite and indirect expressions: "Ich wollte fragen, ob..." (I wanted to ask whether...), "Könnten Sie mir sagen, ob..." (Could you tell me whether...). Using ob-clauses makes your German sound more diplomatic and less blunt.

German speakers sometimes use "falls" (in case) instead of "wenn" for conditions to make the conditional meaning absolutely clear: "Falls du Zeit hast, ruf mich an" (In case you have time, call me).

Practice Tips

1. Transform direct questions into indirect questions with ob: "Ist er da?" → "Ich weiß nicht, ob er da ist." "Hat sie Zeit?" → "Ich frage mich, ob sie Zeit hat." This drills the verb-final pattern.
2. Write five wenn-sentences about your daily life: "Wenn ich aufwache, trinke ich Kaffee. Wenn es kalt ist, ziehe ich eine Jacke an." Practice the inversion in the main clause.
3. Test yourself on the wenn/als distinction by telling a story: use "als" for specific past moments ("Als ich 10 war...") and "wenn" for repeated or hypothetical situations ("Wenn ich Geld hätte...").

Related Concepts

• Subordinate Clauses: weil, dass — the first pair of subordinating conjunctions
• Temporal Subordinate Clauses — more time-related conjunctions like als, während, bevor, nachdem