A parallel structure would be,Originally Posted by Unregistered
Subject+ verb: either you study or you risk
Verb (Imperative): either study or risk
"you study" and "you risk" are not imperative structures. Consider the third person form, Either she studies or she risks failing the exam. The verbs are conjungated (note, -s).
If you don't study now, you might fail the exam.
"fail the exam" is a potential consequence of not studying.