"Grandiose" means extravagant or ambitious. "Burgeoning" means prospering or expanding. "Nonchalant" means easygoing or laid back. "Mellifluous" means smooth and sweet-sounding. "Haughty" means arrogant or snobbish. "Germane" means appropriate or applicable. "Listless" means spiritless or without energy. "Inchoate" means undeveloped or beginning. "Perfunctory" means automatic or unthinking. "Obscure" means not easily understood or ambiguous.

For the first blank, we can infer that because the explorer faced "dangerous jungles filled with vicious predators, poisonous snakes and tropical diseases," she must have been pretty brave, so we need to pick out an answer choice that is an adjective and means something like "brave" to describe her. Either "intrepid" ("fearless; adventurous (often used for rhetorical or humorous effect)") or "courageous" ("not deterred by danger or pain; brave") could be potentially correct. For the second blank, we know that something about the volume's length is "surprising," and that it "only had about thirty pages when most people expected hundreds," so we can infer that we need to pick out an answer choice that is an adjective and means something like "short." Either "brief" ("concise in expression; using few words") or "concise" ("giving a lot of information clearly and in a few words; brief but comprehensive") could be potentially correct. Of the possible words that we've identified as potentially correct for each blank, only "intrepid" and "concise" appear in the same answer choice, so the correct answer is "intrepid . . . concise."

We can infer that because the biology student "was soon corrected when she learned . . . that many of the [zoo's snakes] were extremely poisonous," she must have initially believed them to not be poisonous. So, we need to pick out an adjective for the second blank that means something like "not poisonous." Either "benign" (" not causing harm or damage") or "harmless" ("not able or likely to cause harm") could be potentially correct. Working backwards, then, we might characterize the biology student as uninformed and guess that she is inexperienced if she initially thought that all the snakes in the zoo were not poisonous, so we need to pick out an adjective for the first blank that means something like "uninformed" or "inexperienced." Either "naive" (" showing a lack of experience, wisdom, or judgment" when used of a person or action) or "inexperienced" ("having little knowledge or experience of a particular thing") could be potentially correct. Of the potentially correct answers we've identified, only "naïve" and "benign" appear in a single answer choice, so "naïve . . . benign" is the correct answer.

Considering the first blank, we know that Harry "hadn't expected to place in the top five" in the Science Fair, but ended up "com[ing] in second," so we can infer that Harry was very happy about this and that we need to pick out an adjective to describe him that means something like "very happy." Either "euphoric" ("characterized by or feeling intense excitement and happiness") or "ecstatic" ("feeling or expressing overwhelming happiness or joyful excitement") could be correct. For the second blank, we know that George "had expected to win first prize" but "came in fourth," so we can infer that he wasn't so happy with that turnout. So, we need to pick out another word that means something like "happy." Either "gleeful" ("exuberantly or triumphantly joyful") or "pleased" ("feeling or showing pleasure and satisfaction, especially at an event or a situation") could be correct. Of the possible words that we've identified as potentially correct for each blank, only "euphoric" and "gleeful" appear in the same answer choice, so the correct answer is "euphoric . . . gleeful."

The first blank of this sentence is contrasted with the subordinate clause "taken as  a whole." The general idea is that, while Greta was certain of something concerning the whole reasoning, she was not certain about any given parts of it. That is, she was not certain regarding any specific errors. The word "specific" means distinct or identifiable; it is often contrasted to "general" or "generic." The second blank is best understood in relation to the word "errors in George's reasoning." While she was not certain about any specific parts, she was sure that the reasoning had errors. Thus, among the options provided, the best answer is "illogical," which means "having the character of poor, incorrect reasoning."

The adjective that we choose for the first blank needs to describe texts and have a positive connotation since the intern was hired for her ability to write good explanations. "Lucid" (which means expressed clearly; easy to understand) and "articulate" (which means fluent and coherent when referring to a person's writing) are each good choices for the first blank. For the second blank, we need to pick an adjective that has something to do with the art works' beauty. Choosing between "aesthetic" (concerned with beauty or the appreciation of beauty) and "empirical" (having to do with observation or experience rather than theory), "aesthetic" is the better choice, so the answer is "lucid . . . aesthetic."

In sentences with two blanks it is important to ensure that the meaning of the two blanks work with one another, as well as with the sentence as a whole. From the context of the sentence it is clear that the second blank must be a form of behavior that would get Alice fired. Comely means cute and mandatory required so those two answer choices could be ruled out. Histrionic means dramatic, but being fired from her job would be unlikely to make Alice feel reinforced so we can rule out that option. Merciless means cruel and without mercy, but again being fired is not going to make Alice feel jubilant. That leaves us with only despondent and debauched. Despondent means upset or disappointed, which is a normal reaction to being fired and debauched means wicked or lurid. This answer choice fits.

This sentence explains the relationship between the two blanks by saying that the second opinion is much stronger than the first opinion. This means that the two blanks both have to focus on the same general principle and that the second is an exaggeration of the first. The correct answer is insufferable . . . reprehensible. Insufferable means annoying and unbearable,and reprehensible means very bad and immoral;both are negative implications and the second is stronger opinion than the first. Petulant usually refers to someone ill-tempered, but worthy means someone deserving of praise so that does not fit. Erratic means difficult to predict, which does not match with regressive. Cursory which means done superficially does not fit comfortably into the sentence. Prosaic means ordinary,which also does not fit comfortably.

The contrast in this sentence is between “rigid logic” and the second blank. The word “heuristic” (particularly in computer science) means a loose rule—often explained as being a “rule of thumb.” Such devices help to simulate some scenario but not with the certainty of mathematical logic. For those who are used to such rigid logic, the development of such “heuristics” can be very difficult and perplexing—hence the choice word for the first blank.

A "sophisticated" work is one that is very complex, requiring much experience and knowledge to navigate. Although the word is distantly related to the Greek root “sophia,” meaning wisdom (and found in words like “philosophy”), “sophisticated” had a long development through more negative connotations (partially related to usages like “sophistical”). These are not reflected in our usage here. 

“Colloquial” means related to ordinary speech. Its root is derived from the Latin for “to speak or talk,” which has many derivatives in English, not only including those with the “c” that we see in “interlocutors” (e.g. "locution," "allocution"), but also the more common (and phonetically related) “q” (e.g. "eloquence," "loquacious," "colloquium"). The prefix “col-” really is derived from the Latin “cum,” meaning with. Colloquial language is the language one uses to “speak with” others of similar backgrounds and upbringings.