"Who is my teacher?"
Translation:Quis est magistra mea?
Are you sure it uses "quae" instead of "quis" (who, what) and not instead of "qui" (who, which)? Because as far as I can tell the singular feminine of "qui" is "quae", but both feminine and masculine singular of "quis" is "quis" (with neutral being "quid"), and it only becomes "quae" in feminine plural (that is to say, when referring to several girls or women).
For the accusative singular of the masculine word for teacher.
Masc. acc. plural is
Feminine acc. sing. and plural Would be magistram and magistras.
Wiktionary basicly has all the declensions because your head is gonna be full pretty quickly if you want to learn each word seperately.
Best way is just learn the cases for the dfferent declensions by heart. Because each group follows the same set if rules. Safe a lot of space in your head ;)
(Unfortunately I still have to cheat a bit and look them up, it has been a few years so I only remember half of the list.)