To mark an impression...say "yuk"..

Latest  I have learnt working in here, is that the best way to mark your impression, is to say...shit man he is/she is so yuk...does not know work... And not very much into latest technology.
Talk about my alma mater...the professors who taught and the work i learnt, i was shunned by one line...he taught you this???....shut up! He himself doesn't kno anything.....( This professor has been working for more than 25yrs....and  dean and given huge projects....well may be this guy in my office is a gr8 prodigy...hats off...in 3 years   ....he learnt classy all,.)   So you are mouth shut...and dumbfound...what the hell.....
How can i reply a person so intelligent you kno...and i am left thinking,if my professor 
Is nothing.,,i am just nothing for this colleague ..,,.huh got enough ego for myself anyways...,
What the hell does he kno ! :)