"Чия це тітка?"

Translation: Whose aunt is this?

[StevenLeGe]

How can you tell which form the "Чия" is supposed to be in?

[tomekico]

чий is used for masculine nouns, чия for feminine nouns.
This and more is covered in the "Tips and Notes".

[StevenLeGe]

Ohhh okay thanks!