Sentence completions can be difficult because of vocabulary. But students make them more difficult by approaching them incorrectly. Most students try to force each answer choice until it fits in the sentence. What ends up happening is that it starts to feel like every answer works. So what should you do instead?
The fix is simple: by actively looking for key words or key phrases! The best part is that these keys are ALWAYS CLEARLY and DIRECTLY stated in the problem.
Here's an example:
Answer: C