A review of Lectio 1.1, plus the new forms. So far, easy-peasy. These all work the same as vertebra/vertebrae, nucleus/nuclei, bacterium/bacteria. Please note again that these are still all subjects. When we get these same words, and many others like them, playing different *roles* in their sentences (direct object, indirect object, object of a preposition, et cetera) the *forms* of these words will be different! We did the Nominative ("he/she/they"), Genitive ("his/hers/theirs") and Objective ("him/her/them") cases in English. Latin is arranged just a little bit differently, but here Latin _Casus Nominativus_ and English Nominative Case are the same!