how long / you / be in this class?
How long have you been in class?
How long / you / live in Belo Horizonte?
How long have you lived in Belo Horizonte?
How long / we know / the teacher?
How long have known the teacher?
How long / you study/ at your school?
How long have you studied at your school?
How long / the world / be / under the Covid-19 pandemic?
How long was the world under the Covid-19 pandemic?
how long / you / study / at Cultura Inglesa?
How long have you studied at Cultura Inglesa?