Separable or inseparable? When stress changes the meaning (voorkomen)

A small group of Dutch compound verbs is spelled the same but behaves in two ways. Where you put the stress decides both how the verb splits and what it means. Compare Deze klacht komt vaak voor (This complaint is common) with Zij voorkomt een ongeluk (She prevents an accident): the same letters, voorkomen, but two verbs.

Say the word aloud: if you hit the prefix hardest, the verb is separable; if you hit the verb part hardest, it is inseparable. On this page the stressed part is written in capitals to show the difference.

1. Stress on the prefix → separable. In a main clause the prefix breaks off and moves to the end: De zon gaat onder. (The sun is setting.) The past participle slots ge- between the prefix and the stem: onder + ge + gaan = ondergegaan.
2. Stress on the verb → inseparable. The prefix never leaves the stem: Zij ondergaat een operatie. (She is having an operation.) The past participle takes no ge-: ondergaan (the same letters as the infinitive).

There is a pattern behind the two readings. When the prefix still points to a real direction or place — down, over, through — the verb tends to split. When the prefix has drifted into an abstract idea, the verb tends to stay whole. That is why ONDERgaan (to go down) splits, while onderGAAN (to undergo, an abstract kind of going under) does not.

The past participle is where the two forms look most different: separable voorgekomen, ondergegaan, overgekomen, doorgelopen, but inseparable voorkomen, ondergaan, overkomen, doorlopen with no ge- at all.

Only a limited set of prefixes can sit on either side of the split. Verbs with any other prefix (op-, uit-, mee-, aan- in its literal use) are separable, and the fixed unstressed prefixes be-, ge-, ver-, ont-, her-, er- are always inseparable.

• Ten prefixes are two-faced this way. Six of them — door-, om-, over-, onder-, voor- and aan- — head verbs that lean toward splitting, though each also has inseparable members. Two others, mis- and vol-, lean the opposite way and are usually inseparable. The last two, achter- and weer-, turn up in only a handful of verbs each. Whichever prefix it is, stress stays the test, and a dictionary settles the doubtful cases.
• With mis-, the reading points the way. When it paints the whole action as going wrong or badly, the verb is inseparable: misbruiken (to misuse), misverstaan (to misunderstand), mishandelen (to mistreat). When it means a plain physical miss — aim or grip that does not land — the verb splits: misgooien (to throw and miss), misgrijpen (to grab and miss).
• vol- behaves the same way. In its abstract sense of carrying something through to the end it stays fused: voltooien (to complete), voldoen (to satisfy, to meet a requirement). When it just means filling something to the brim it splits: volgooien (to fill right up), volschenken (to fill a glass).

The common error is treating one meaning as if it were the other. Ik voorkom een ruzie means I prevent a quarrel (inseparable, voorkom stays whole); writing Ik kom een ruzie voor is wrong, because the separable VOORkomen means to occur and does not take an object. In the past participle, do not add ge- to an inseparable verb: to undergo an operation is Zij heeft een operatie ondergaan, never ondergegaan — that split form belongs to the sun setting (De zon is ondergegaan).