"Livia is not a man."
Translation:Livia non est vir.
We are working on adding them. Bear in mind that the course has barely been out and so a lot of things will be missing, the best way to help get them fixed as quickly as possible is to use the report button in the lesson (and not comment about the answer in the discussion unless there are questions about whether or not it's acceptable). Also be aware that unfortunately the changes we make don't show for users right away, sometimes it takes up to two weeks (though it's usually faster than that).
Having said all that, the verb should be "est", not "es".