Last summer
I am in the 5th grade of the medical school.
Scince I will have to serch some training hospitals where I can work as a intern next summer,this is the last summer can find some free time.
And, this means this is the last sommer vacation as a student.

I had planned to read some books,such as Robbins Pathologic basis of disease every time before vacation,I have faild to accompanish that.