After running twenty-six miles, the runner is likely very tired; key words like "stumbling" show that he or she barely made it. So, we need to pick out an answer choice that means something like very tired. While you might think that "buoyant," and adjective that means either able to float or cheerful, could be a potentially correct answer because the runner might feel happy that he or she has compelted the race, the context clue contained in "After running twenty-six miles over mountainous terrain" suggests that the adjective should refer to the athlete being very tired, not very happy. So, the word that best fits the sentence is "fatigued," which means exhausted. As for the other answer choices, "sorrowful" means very sad; "fervent" means passionate or enthusiastic, and "mortified" means very embarassed.

We can infer that because the speaker's uncle "can spend hours talking," he must be very talkative. So, we need to pick out an answer choice that means something like talkative. So, that means that neither "shy" nor "quiet" cannot be the correct answer, because each of these words is an antonym of talkative, and neither would make sense as describing the uncle discussed in the sentence. The word that best fits the sentence is "garrulous," which means talkative or loquacious. As for the other answer choices, "explosive" can mean incendiary, touchy, or sudden, and "assured" means confident.

We are told that the invention is "clever" and that it "amazed engineers for centuries," so we need to pick out an adjective to describe the invention that means something like clever. That means that "stale" cannot be the correct answer, as "stale" in this context would mean hackneyed or trite, so a "stale" invention would not amaze anyone. The best answer choice is "ingenious," an adjective that means possessing or demonstrating great creativity and cleverness. As for the other answer choices, "ephemeral" and "transitory" both mean temporary or lasting for a short time, and "futile" means useless or pointless.

For our purposes, the key word in the sentence is "blood-spattered," which tells us that the crime scene is gross and that violence has occurred there. So, we need to pick out an answer choice that means something like gross or suggesting that violence has occurred. The word that best fits the blank is "gruesome," which means grisly or horrible. As for the other answer choices, "blessed" means holy or sacred, "unconventional" means departing from what is traditional or expected; "quaint" means old-fashioned in a charming way; and "placid" means calm or even-tempered.

The main idea here is the host's energy and enthusiasm; he doesn't stop entertaining even when everyone else is tired. So, we need to pick out an adjective that means something like energetic or enthusiastic. The word that best fits the blank is "ebullient," which means overflowing with fervor and high spirits or full of excitement. As for the other answer choices, "wise" means knowledgeable or intelligent, "perturbed" means annoyed, "feeble" means weak, and "dogmatic" means authoritarian, imperious, or inflexible.

We are told that it "took researchers months to track [the crocodile] down," and if something takes months to track down, it's hard to find. So, we need to pick out an answer choice that means something like hard to find. While "vicious" might look like a potentially correct answer because one might expect a crocodile to be described as "vicious," the sentence concerns how the crocodile is difficult to track down, not how vicious or not vicious it is. So, the word that best fits the blank is "elusive," which means evasive or hard to find. As for the other answer choices, "agreeable" means friendly or amiable, "eminent" means well-respected or renowned, and "eccentric" means anomalous or unconventional.

This wary and suspicious art collector has reason to doubt the authenticity of this painting. The wonderful word "dubious" means doubtful or suspect, and is thus the best fit. "Unequivocal" would mean very much the opposite: it would be clearly and undeniably authentic. The painting also might be "beguiling" (enchanting) and "inestimable" (priceless), but these qualities would not raise any suspicions for this art collector.

The most appropriate word for the sentence is "intransigent," because "instrangient" means both stubborn and belligerent, which is how one might describe the candidate who is the subject of the sentence. "Despicable" (detestable) might describe the sentence's subject, but not as precisely, while "amiable" (friendly, relateable, agreeable), and "considerate" (thinking of others) are entirely off. "Spiteful" (vindictive) makes some sense in this context, but not as much as "intransigent."