To be honest, I am not sure exactly how the Certificates comapre to America.
All I know is that for Civil Engineering here, you study for 4 years and get a BEng Degree (Basic Engineering, I think). In those 4 years, if you are performing well enough, you can take the last year and study for a MEng Degree (Mechanical Engineering)
It is all beyond me at the minute but should make sense soon.