Als, Wenn, Wann or Ob
'Als', 'wenn', 'wann', and 'ob' are often confused because they can all relate to time or conditions, but they have distinct uses.
'Als' means 'when' (past) or 'than' (comparison).
'Wenn' means 'when' (present/future) or 'if' (condition).
'Wann' means 'when' (question word).
'Ob' means 'whether' or 'if' (indirect question).
This lesson explains when to use each one correctly.
Explanation
'Als' (when) is used for single past events: 'Als ich jung war' (When I was young). Also used for comparison: 'größer als' (bigger than).
'Wenn' (when/if) is used for repeated events or conditions: 'Wenn es regnet' (When/If it rains). Also for present/future: 'Wenn ich komme' (When I come).
'Wann' (when) is a question word used in direct and indirect questions: 'Wann kommst du?' (When are you coming?), 'Ich frage, wann du kommst' (I ask when you come).
'Ob' (whether/if) introduces indirect yes/no questions: 'Ich frage, ob er kommt' (I ask whether he comes).
Rule: Past single event → 'als', repeated/present/future → 'wenn', question → 'wann', yes/no question → 'ob'.
Als, Wenn, Wann, Ob - Usage Guide
| Word | Meaning | Use | Example | Translation |
|---|---|---|---|---|
| als | when (past) | Single past event | Als ich jung war, lernte ich Deutsch | When I was young, I learned German |
| als | than | Comparison | Er ist größer als ich | He is bigger than I |
| wenn | when/if | Repeated/present/future | Wenn es regnet, bleibe ich zu Hause | When it rains, I stay home |
| wenn | if | Condition | Wenn ich Zeit habe, komme ich | If I have time, I come |
| wann | when | Question word | Wann kommst du? | When are you coming? |
| ob | whether/if | Indirect yes/no question | Ich frage, ob er kommt | I ask whether he comes |
Examples
Als ich jung war, lernte ich Deutsch.
When I was young, I learned German. (past single event)
Er ist größer als ich.
He is bigger than I. (comparison)
Wenn es regnet, bleibe ich zu Hause.
When it rains, I stay home. (repeated/present)
Wenn ich Zeit habe, komme ich.
If I have time, I come. (condition)
Wann kommst du?
When are you coming? (question)
Ich frage, wann du kommst.
I ask when you come. (indirect question)
Ich frage, ob er kommt.
I ask whether he comes. (indirect yes/no question)
Common Mistakes
Wenn ich jung war
Als ich jung war
For single past events, use 'als', not 'wenn'.
Als es regnet
Wenn es regnet
For present/future or repeated events, use 'wenn', not 'als'.
Ich frage, wenn du kommst
Ich frage, wann du kommst
In indirect questions asking 'when', use 'wann', not 'wenn'.
Ich frage, wann er kommt (for yes/no question)
Ich frage, ob er kommt
For indirect yes/no questions, use 'ob' (whether), not 'wann' (when).
Practice Exercises
Test your understanding with interactive exercises. Practice makes perfect!
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Frequently Asked Questions
How do I know which article to use?
German articles (der, die, das) depend on the gender of the noun. While there are some patterns, many nouns must be memorized. Practice and exposure to German will help you learn them naturally.
What's the difference between definite and indefinite articles?
Definite articles (der, die, das) mean 'the' and refer to specific things. Indefinite articles (ein, eine) mean 'a/an' and refer to non-specific things. Both must match the noun's gender: use 'ein' for masculine/neuter and 'eine' for feminine.
Are there rules for determining noun gender?
While there are some helpful patterns (e.g., words ending in -ung are usually feminine), there are many exceptions. The best approach is to learn nouns with their articles from the beginning.
What happens if I use the wrong article?
While using the wrong article is a common mistake, native speakers will usually still understand you. However, using the correct article is important for sounding natural and fluent in German.