Language/Volapuk/Grammar/past

The past tense (the preterite) is formed by also removing -ön from the infinitive, then by prefixing ä- to the beginning. (If you want to bring the past more into the present (that is to use the present perfect), put e- at the beginning); finally add the necessary personal pronoun to the end:

• Älöfol-li hipuli? ‘Did you (use to) love the boy?’
• Elöfol-li hipuli? ‘Have you loved the boy (up to now)?’
• Äpenob penedi ‘I was writing a letter’
• Epenob penedi ‘I have (already) written a letter’
• No äslipom in bür ‘He wasn't sleeping in the office’
• No eslipom in bür ‘He hasn't slept in the office (up to now)’
• Äseadob ‘I sat; I used to sit; I was sitting; I did sit’
• Eseadob ‘I sat; I have sat; I have been sitting’
• No ävilobs ‘We didn’t want; we weren’t wanting’
• No evilobs ‘We haven’t wanted (up to now)’

Source: http://www.xn--volapk-7ya.com/quick-look-at-volapuk.html