A common shortcut on Sentence Equivalence questions is to dive directly into the answer choices, and pick a pair that matches. This can be an effective strategy, especially when the sentence itself is complicated, and you find yourself scratching your head. To follow this strategy indiscriminately – that is, to never read the sentence, but to always look directly at the answer choices – is fraught with dangers, with very low probability of choosing the correct answer choices.
Sometimes, there are two pairs of synonyms, so you will need to read through and analyze the sentence, coming up with your own word.
Unless you are running out of time, you should always read a Sentence Equivalence question first, and try to come up with your own word.It is the best possible strategy in any kind of Sentence Equivalence Question. Only if you are stuck should you resort to the strategy described above.
Have a go at the following sentence:
Brutus is often held up as the embodiment of ______–-yet, while it is true that he deceived his friend, Julius Caesar, one must not forget that Caesar had become both a danger to himself and the Republic.
(A) wisdom
(B) prudence
(C) treachery
(D) selflessness
(E) perfidy
(F) cowardice

Explanation:

If you dive straight into the answer choices, then answers (A) and (B) create synonymous sentences. If you plug those answer choices in, they would seem to work, as well. After all, Caesar had become so problematic that it was prudent on Brutus’s part to dispatch the megalomaniacal leader.’
But, if we read the sentence carefully, we will notice that the clue is “deceived his friend”. The rest of the sentence is trying to convince the reader not to think of Brutus as the embodiment of deception (our own word). Therefore, we need two synonyms that mean deception. The word treachery, which means disloyalty/deception, is an obvious match.
For the final answer choice, though, we have to be more careful. You may be tempted to pick cowardice. But, remember, we need similar words that create similar sentences. To say that someone who is a coward is always disloyal is clearly untrue. So, do not be afraid to pick answer choice (E) perfidy, just because you are not sure what it means. (D) selflessness is clearly not the answer as it doesn’t match our word, nor the context of the sentence. Therefore, (E) perfidy has to be the answer.
Perfidy is a synonym for treachery, and is also a high-frequency GRE word, so make sure you know it.

Takeaways:
Always read the sentence, and try to come up with your own word. Only if you are unable to do so should you attempt to pick synonym pairs. Instead, come up with your own word, and make sure the two answers are similar words.