Help with yet anoth SQL querie

Hi
I need help with a sql queries
here's the deal my table:

Student_Id,Course_ID,Term(A OR B) , ExamDate,Simmester(Winnter,summer),Grade.

A student has more then one Course and can take both terms of the exam regardless to the grade on the first exam. the last term exam is the one that counts. both grades(term A and B) are kept. and some Course has 2 exams (one in the winnter and summer --- meaing a student can have up to 4 lines in the table for that Course)

I want to make a select querie to display the last results of the exams only -- if the Course is 2 Simmester it will display the last grade from the first grade Winnter Simmester AND the last grade summer Simmester . for each Course

10x