"Aamir is outside since quarter past four."

Translation: आमिर सवा चार बजे से बाहर है।

[mayateacher]

In English, if you use SINCE you have to use HAS BEEN, i.e. Aamir has been outside since 4:15.

[koolAanvi]

Can't you also say that "save chair base se Aamir bahar he."

[RInspired]

Yes, you can say that but Duo does not accept it.