[quote=bsk_syh;386803]I am a university student and i have just read a phrase which is
Watch out!Speed bumps ahead!
A 'speed bump' is a low rounded bit of pavement protruding from the driving surface and extending from one side of a street to the other. It's marked by a warning sign and usually painted yellow to be more noticeable. Its purpose is to force motorists to reduce speed in order to drive over it without damaging their cars. Speed bumps are often placed in residential areas, to keep the traffic safer and less noisy.
'Speed bump' is also used idiomatically to mean anything that slows the progress of a project.
I hope this helps,
PS If you go to google images there are probably lots of photos of speed bumps.