Last week in Comp Sci

Last week we took two quizzes and started to move back into the regular schedule for comp Sci. I did well on one of the quizzes, but I did rather badly on the array quiz. I do not understand how array shortcuts work. I know the general idea of putting a semicolon in between the variable name and the array, but I do not understand how to manipulate and use the array afterward. I missed 2 questions on my quiz because of this and I will have to go in during lunch to figure out why. I know these will be on the AP so it is pretty important that I figure out how they work, but I will be glad to move on to a new topic and hopefully one I will understand a bit better.