duo, duärum, duo
The number "two" is inherently plural, so its
declension only has plural forms. The declension is irregular, however,
especially in the NPM and NPF and in the dative and ablative
The trick with this paradigm is to remember the NPM and NPN have the form "duo" and that the vowel that marks the gender (ö for masc and neut; long a for fem) persists in the dative and ablative (i.e., you don't get the 'ibus' endings you would expect).
Chapter 15 index/ Drill 1/ trës