MANCOVA statistics: Query

I am trying to conduct repeated measures MANCOVA in SPSS software, where I need to measure my dependent variable at 4 periods of time (years). Also, the dependent variable at each year is related with 2 independent variables. To be honest, it is a very complicated for me, I am unable to understand the concept of MANCOVA and running it on SPSS is the icing at the top. Any help regarding this would be really appreciated.