Bleh, Ugh, Bleh

Well we are well into the fall semester and let me just say I am doing way better in Biology than Spanish. I just cant seem to pick up on Spanish. If I see a sentence and I have to fill in blanks I am good to go but when I have to form the sentence... thats where I am faltering. I do not understand why I am not getting it. I got 80% or higher on every set of assignments... exactly 80% on assignment group 3. That was the biggest group of assignments at 91. The other 2 were 85% or higher. Still B work. But being gone and missing a quiz, an exam, and 2 book assignments it has me at an F. It doesn't make sense. Can someone figure it out for me please? Thank you!