't kofschip

The 't kofschip (Dutch pronunciation: [ət ˈkɔfsxɪp], the ) or 't fokschaap rule is a mnemonic that determines the endings of a regular Dutch verb in the past indicative/subjunctive and the ending of the past participle. This rule should not be confused with the so-called T-rules (t-regels).

The rule goes as follows:

If the verb-root ends in one of the consonants of 't kofschip, being ⟨t⟩, ⟨k⟩, ⟨f⟩, ⟨s⟩, ⟨ch⟩, and ⟨p⟩, the past tense ends in -te(n) and the past participle (voltooid deelwoord) in -t. If the verb-root ends in any other consonant or in a vowel, the past tense ends in -de(n) and the past participle in -d.

For example:

Because of the idiosyncrasies of Dutch spelling, some forms are spelled in unexpected ways. The past tense forms of proeven and blozen are written with f and s, as Dutch spelling rules permit the letters v and z only at the beginning of a syllable; however the pronunciation remains /v/ and /z/. Words may not end in a double consonant, so the past participles gerust, geland and gered do not get an additional -d. See Dutch orthography for more information.

Because of regular final-obstruent devoicing, the past participle ending is pronounced with a voiceless /t/ even though d is spelled. When the participle is inflected (in accordance with a following noun), the devoicing is undone, like in other words. Thus geland /ɣəˈlɑnt/, geleegd /ɣəˈleːxt/, geproefd /ɣəˈpruft/ inflect to gelande /ɣəˈlɑndə/, geleegde /ɣəˈleːɣdə/, geproefde /ɣəˈpruvdə/ respectively.

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