COLREGS_Term impede explained along with example and situations 

Sorry to hear about this. Nevertheless failing in oral exam is very often and it can happen to any one.Do let me know whether this kind of video is able to help in your next attempt.Perhaps you need to take care of other reasons as well and be confident. Usually a reuired level of confidence is achived only after enough of practice under able guidance or a well planned self study.

This concept is very important and not so clear among candidates, this was very helpful.