I've been reading through the first two chapters of Lingua Latina and spotted something that doesn't seem right. In Chaper II, the reader is asked "Quis est Marcus?", with the Interrogative Pronoun used. A sentence later, and we're asked "Quae est Iulia?", which seems to incorrectly utilise the Interrogative Adj. Shouldn't "Quis" be used to formulate both questions?