Chapter 9, Drill a: Drill genitive case endings.

For each Latin noun, give the singular or plural genitive, as requested. Remember that third declension i-stems so far are those whose nominative singular, as well as genitive singular, end in -is and have the same number of syllables (although not canis or iuvenis), and those whose stems end in two consonants.

Example:
puella (singular) Answer: puellae.