Some roots are misleading. Over the centuries, they have taken on different meanings or are not roots at all, but part of a larger verb. Mis-, with one exception below, negates what follows it. To align something is position it correctly; to misalign is to move it out of position. So if you know what follows the mis- below, you’ll likely know the meaning of the word.
A word that often comes up in politics, misappropriate means to unfairly or illegally take something. Often times you’ll read about some public official misappropriating funds. Basically, that person’s role was to collect money for some cause or project and in doing so a little money (or sometimes a lot!) was skimmed from the top.
To appropriate, in the same context, means to hand out or give money. Interestingly, to appropriate can also mean to take something without permission—though it doesn’t carry the same denotation of illegal that misappropriate does.
To apprehend doesn’t just describe the police taking a suspect into custody. To apprehend can also mean to understand, as in our apprehension of our surroundings depends on our mental state. To misapprehend is to misunderstand. I can misapprehend what somebody is trying to say if I don’t pay close attention to his or her words.
An interesting word root-wise, in that is has slightly changed in meaning, a miscreant was originally a heretic (creant comes from the Latin for believe). Today, however, miscreant is used to describe anybody who breaks the law in a bad way (no mere speeding tickets here).
To misconstrue is to misinterpret. You might misconstrue a person’s behavior and think that person intends to do something he or she actually doesn’t. Often when driving, we misconstrue the actions of other drivers. A person in front of you might cut you off since he is running late. Of course, you’re apt to misconstrue such an impetuous maneuver as the handiwork of a miscreant.
A clear exception to the ‘mis-‘ rule, missive comes from the Latin to send—a very apt meaning. A missive is a formal letter. It’s not a typical GRE word and I can’t imagine it turning out as the correct answer. However, it might in some cases make for a very good distractor.
This word does not describe a petty person who wants to take a gift back. A misgiving is that mixture of doubt and unease about how something will turn out. You’d be right to have misgivings about walking in cold turkey to take the GRE. Each election cycle part of the population has deep misgivings about how the incumbent will serve.