From cyd- (“together, co-”) + sefyll (“stand”).
cydsefyll (first-person singular present cydsafaf)
| singular | plural | impersonal | ||||||
|---|---|---|---|---|---|---|---|---|
| first | second | third | first | second | third | |||
| present indicative/future | cydsafaf | cydsefi | cydsaif | cydsafwn | cydsefwch, cydsafwch | cydsafant | cydsefir | |
| imperfect (indicative/subjunctive)/ conditional |
cydsafwn | cydsafit | cydsafai | cydsafem | cydsafech | cydsafent | cydsefid | |
| preterite | cydsefais | cydsefaist | cydsafodd | cydsafasom | cydsafasoch | cydsafasant | cydsafwyd | |
| pluperfect | cydsafaswn | cydsafasit | cydsafasai | cydsafasem | cydsafasech | cydsafasent | cydsafasid, cydsafesid | |
| present subjunctive | cydsafwyf | cydsefych | cydsafo | cydsafom | cydsafoch | cydsafont | cydsafer | |
| imperative | — | cydsaf | cydsafed | cydsafwn | cydsefwch, cydsafwch | cydsafent | cydsafer | |
| verbal noun | cydsefyll | |||||||
| verbal adjectives | cydsafedig cydsafadwy | |||||||
| Inflected colloquial forms | singular | plural | ||||
|---|---|---|---|---|---|---|
| first | second | third | first | second | third | |
| future | cydsafa i, cydsafaf i | cydsafi di | cydsafith o/e/hi, cydsafiff e/hi | cydsafwn ni | cydsafwch chi | cydsafan nhw |
| conditional | cydsafwn i, cydsafswn i | cydsafet ti, cydsafset ti | cydsafai fo/fe/hi, cydsafsai fo/fe/hi | cydsafen ni, cydsafsen ni | cydsafech chi, cydsafsech chi | cydsafen nhw, cydsafsen nhw |
| preterite | cydsafais i, cydsafes i | cydsafaist ti, cydsafest ti | cydsafodd o/e/hi | cydsafon ni | cydsafoch chi | cydsafon nhw |
| imperative | — | cydsafa | — | — | cydsafwch | — |
| Note: All other forms are periphrastic, as usual in colloquial Welsh. | ||||||