Why is this in a past tense section?
It is not in the past tense. Read it again
I like that they throw these present tense sentences in there to keep us on our toes. It forces us to focus on the conjugation.
Good point. But it also highlights that "atrás" can be "after", "behind", "ago", ...
Why is "We go behind your mother." not accepted?
How would be ,,we are going behind your mom" then?
Literally that would be the case, but we use "ir atrás" as "look for"
Why not "nos vamos atrás DA sua mãe"?
It's also right.
We isn't "we follow..." accepted?
behind is also correct, isn't it
Why is it not "atrás DA sua mãe"?
What does this sentence mean? It doesn't give a translation.
Literally: be after someome (we are after your mother)
It also means (and more probable) "to look for".
I'm sure the translation wasn't there before...
Did you know in English "we are after" can also mean we are looking for? Sometimes meant in a menacing way. "We're after your brother...." (to give him a smack)
Yes, and in Portuguese ir atrás has both negative and positive meanings! ;)