The singular form of the word "possum" is possum. The plural is possums.
The singular form of the word flagella is flagellum.
Criterion is the singular form of criteria.
The word 'duo' is the singular form; the plural form is duos.
The singular form of the word "señores" is "señor."
That is the singular form; the plural form is those.
The singular form is commando.
'Jackhammer' is the singular form.
The singular possessive form of jury is jury's
The word dog is the singular form.
The word "biopsies" is the plural form of the word. The singular form is "biopsy."
The singular form of Sioux is "Sioux." It is both the singular and plural form of the word.
Poteram is a form of the verb possum ("to be able to"); its parse is first-person singular imperfect active indicative, and thus is (standing alone) translated as "I was able to".