How do German separable verbs work?
A separable verb splits in a main clause: the stem is conjugated in its normal position and the prefix goes to the end. Because the prefix often changes the meaning completely, you cannot know what the sentence means until the last word — which is why they are far harder to hear than to read.
The prefix goes to the end
In a main clause in the present or simple past, the prefix detaches and travels to the end of the clause. In a subordinate clause the verb goes to the end anyway and the prefix reattaches to it.
Ich rufe dich morgen an.
I'll call you tomorrow.
anrufen, split.
Ich stehe um sieben auf.
I get up at seven.
aufstehen, split.
…, weil ich um sieben aufstehe.
…because I get up at seven.
Rejoined in a subordinate clause.
The prefix carries the meaning
This is why they matter. One stem plus different prefixes produces genuinely unrelated verbs, so hearing the stem tells you very little until the prefix lands. Kommen alone is to come; the prefixed forms range from arriving to escaping to occurring.
ankommen
to arrive
mitkommen
to come along
vorkommen
to occur, to happen
entkommen
to escape
Inseparable — ent- never splits.
Which prefixes separate
Separable prefixes are stressed and are usually recognisable as prepositions: an, auf, aus, ein, mit, nach, vor, zu, ab, bei. Inseparable prefixes are unstressed and never split: be, emp, ent, er, ge, miss, ver, zer. The stress is the reliable signal, which is why hearing the word tells you more than seeing it.
ánrufen → ich rufe an
stressed prefix, separates
verstéhen → ich verstehe
unstressed prefix, stays put
übersetzen
to translate / to ferry across
Stress alone decides which — and whether it splits.
Common mistakes
Ich anrufe dich.
Ich rufe dich an.
In a main clause the prefix must go to the end. Keeping it attached is one of the most audible learner errors.
Ich habe angerufen dich.
Ich habe dich angerufen.
The participle goes last, and ge- sits between prefix and stem: angerufen.
…, weil ich rufe dich an.
…, weil ich dich anrufe.
A subordinate clause sends the verb to the end and the prefix rejoins it.
Frequently asked questions
How do I know if a verb is separable?
By the stress. Separable prefixes are stressed and inseparable ones are not, so hearing the word settles it. In writing, the separable prefixes are largely the ones that also exist as prepositions.
Why are separable verbs hard to listen to?
Because the meaning is not determined until the prefix arrives at the end of the clause. You have to hold the sentence open, and if the clause is long the prefix can be a dozen words away from its stem.
What happens in the perfect tense?
The ge- goes between the prefix and the stem — anrufen becomes angerufen, aufstehen becomes aufgestanden. Inseparable verbs take no ge- at all: verstehen becomes verstanden.