A lot of verbs in English have fixed adverbial complements and a comparable association often hlods in Dutch. Compare:
the bomb went off.
de bom ging af.
the light went on.
het licht ging aan.
In English one could consider to go off as the infinitive of a distinct verb. In Dutch the association is even stronger, because in some of the forms of such a verb, e.g. the infinitive, the abverb af is actually written as a prefix:
the bomb will go off.
de bom zal afgaan.
This means that there are two types of prefixes to a Dutch verb: inseparable ones (such as be-) and separable ones (like af-). The first kind we have seen before:
bedoelen - to mean
hij bedoelde
hij heeft bedoeld
afgaan
het ging af
het is afgegaan.
Notice that the separable verb does take the ge- marker of the past participle whereas the inseparable ones do not.
There is another difference, at least in the spoken language: the accent of the word lies on the prefix if it is separable, i.e. one says AFgaan, but beDOElen.
Some prefixes can occur both separably and inseparably such as door- (through, by) and voor- (for,before) and in some cases there are two different verbs that look deceptively the same, one separable, the other not, with different meanings. In the spoken language they differ by wordaccent, but this is not visible in the written one unless accents are deliberately added to avoid confusion. Compare:
VOORkomen - kwam VOOR -VOORgekomen - to occur
voorKOmen - voorKWAM - voorKOmen - to prevent
de kluut komt meer in Nederland voor dan in Engeland.
wij moeten er het verdwijnen van zien te voorkomen.
the Avocet is more numerous in the Netherlands than in England. (lit:.. occurs more in NL than..)
we have to prevent its disappearance.
Notice that just like in the case of the pronominal adverb ervan that translates its, the two parts of the separable verb can end up rather far apart in the sentence.
Another example:
een school DOORlopen - to walk through a schoolbuilding (takes 5 minutes)
een school doorLOpen - to absolve one's education at a school (takes 5 years).
Content is available under GNU Free Documentation License Source: Wikibooks