The issue with which Frau Büchlein is concerned appears to be “central” to the topic. When something is “pivotal” it is of crucial importance. It is related to the word “pivot,” which is the central point at which something or someone turns. When a person in a marching band “pivots” he or she turns at a given point. In a mechanism, the pivot point is the point at which something turns in the thing’s motion. When applied metaphorically, it means “central” in the sense above, namely, “centrally important” or “crucially important.” When someone has “keen” awareness, he or she has very sharp or developed awareness.

For the first blank, we need to pick out an adjective that could potentially describe a "knight who roams the countryside winning tournaments and protecting travelers from . . . beasts like wolves and bears." Either "redoubtable" ("of a person: formidable, especially as an opponent") or "formidable" ("inspiring fear or respect through being impressively large, powerful, intense, or capable") could be potentially correct. For the second blank, we need to pick out an answer choice that means something like "dangerous" to describe the "beasts like wolves and bears" from which the travelers need protecting. Either "fell" ("of terrible evil or ferocity; deadly") or "ferocious" ("savagely fierce, cruel, or violent") could be a potentially correct answer choice. Of the potentially correct answers we've identified, only "redoubtable" and "fell" appear in a single answer choice, so "redoubtable . . . fell" is the correct answer.

For the first blank, we need to pick out an adjective that means something like "unable to be depended upon," because we know that Todd "never turned his assignments in on time and sometimes never turned them in at all." Either "inconstant" ("of a person or their behavior: not faithful and dependable") or "unreliable" ("not able to be relied upon") could be potentially correct. For the second blank, we need to pick out an adjective that means something like "blunt," because one can assume that a talk where the group would tell Todd that "the group's other members wanted him to leave" would be pretty blunt. Either "straightforward" ("uncomplicated and easy to do or understand") or "frank" ("open, honest, and direct in speech or writing, especially when dealing with unpalatable matters") could be potentially correct. could be potentially correct. Of the possible words that we've identified as potentially correct for each blank, only "inconstant" and "frank" appear in the same answer choice, so the correct answer is "inconstant . . . frank."

The greatest level of debt would be created by spending a lot while taking in very little money (Econ 101). An "opulent" lifestyle would involve many expensive and fancy things, and a "modest" income means a relatively small one (NOT an income that doesn't brag or doesn't show a lot of skin). A "lavish" lifestyle might create debt, but probably not with an "imponderable" (beyond comprehension . . . in this case implying a huge sum) income; likewise, a "diminutive (very small) income might create some debt, but if the couple was living "sensibly" (in this sense, within or close to within their means), their debt would not likely be very large.

For the first blank, we're looking for a verb that means surprised, since Harry had only ever heard Jane speak English in front of him. Both "astonished" and "astounded" are good choices for the first blank, so we're left to decide between "fluent" and "corporeal" for the second blank. For this blank, we're looking for an adjective that describes Jane's ability to speak multiple languages. Since "fluent" means able to speak or write in a language nearly as well as a native speaker of that language, and "corporeal" means having to do with physical instead of spiritual things, "fluent" is the better choice, and the answer is "astonished . . . fluent."

For the first blank, we need a verb that means something like serious to describe the threat the villagers face. Either "grave" or "significant" could work, which leaves us to choose between "hysterical" (uncontrollably emotional) and "tender" (gentle and sympathetic) for the second blank. For this latter blank, "hysterical" is the better choice to describe the emotional villagers that needed soothing, making the right answer "grave . . . hysterical."

Since the student's assignment was full of careless errors, we can infer that we are looking for an adjective that means something like minimal or lazy. Either "lackadaisical" (lazy and careless) or lax (not careful enough) could be correct. For the second blank, we can infer that the teacher thinks the student will work more diligently on a topic that interests the student more, so we're looking for an adverb that means something like diligently. Either "sedulously" (in a dedicated fashion) or "fastidiously" (meticulously) could work. Of the potential answer choices we've identified, only "lackadaisical" and "sedulously" line up in a single answer choice, so the answer is "lackadaisical . . . sedulously."

Since the morning is described as cold, damp, and foggy, we can infer that we need to pick a word for the first blank that means something like gloomy. Either "bleak," which means miserable and chilly, or "dreary," which means depressing, could work. For the second blank, we can tell that since the fog quickly dissipated, we need to pick an adjective that means something like fleeting. Either "ephemeral" or "evanescent" could work, as each word can mean existing only temporarily. Of the possible words that we've identified as potentially correct for each blank, only "bleak" and "evanescent" appear in the same answer choice, so the correct answer is "bleak . . . evanescent."

We can infer from the sentence's context that the first attempts to cross-breed the two types of wheat were unsuccessful, as the geneticist "eventually succeeded." So, for the first blank, we're looking for an adjective that means something like failed. Either "fruitless" (unproductive) or "futile" (pointless) could work. For the second blank, we need to find an adjective that describes the plant produced from the cross-breeding of two species of wheat; either "hybrid" (an organism produced by crossing two species or types) or "cross-breed" could be correct. Of the possible words that we've identified as potentially correct for each blank, only "fruitless" and "hybrid" appear in the same answer choice, so the correct answer is "fruitless . . . hybrid."

Let's start with the second blank. From the examples of "beads and links of chain," we can infer that the archeologists are looking for small artifacts, so we need to find an adjective that means "very small." Either "minuscule" or "puny" could work. For the first blank, we're looking for a verb that means to uncover, since the rest of the sentence refers to displaced dirt. In choosing between "excavated" and "exonerated," "excavated" is the better choice, since it means carefully removed dirt from an area, while "exonerated" means cleared from blame.