If a female losing her virginity is by a "p" entering her, then if she's she can't lose her virginity?

Not really. By the definition the teacher gave you, that means they can't lose their virginity. However, they still have other forms of . A lot of people, myself included, see , , and any other ual act as . There's a reason they're described as ual acts. No one should fool themselves into thinking they're a virgin when they give their boyfriend even if by that definition you gave, they are. You can't really say someone's a virgin when they are doing everything but to satisfy their ual desires.