Tunas, mackerels, and billfishes (marlins, sailfishes, and swordfish) swim continuously. Feeding, courtship, reproduction, and even “rest” are so carried out while in constant motion. As a result, practically every aspect of the body form and function of these swimming “machines” is adapted to enhance their ability to swim. 

    Many of the adaptations of these fishes serve to reduce water resistance (drag). Interestingly enough, several of these hydrodynamic adaptations resemble features designed to improve the aerodynamics of high-speed aircraft. Though human engineers are new to the game, tunas and their relatives evolved their “high-tech” designs long ago. 

    Tunas, mackerels, and billfishes have made streaming into an art form. Their bodies are sleek and compact. The body shapes of tunas, in fact, are nearly ideal from an engineering point of view. Most species lack scales over most of the body, making it smooth and slippery. The eyes lie flush with the body and do not protrude at all. They are also covered with a slick, transparent lid that reduces drag. The fins are stiff, smooth, and narrow, qualities that also help cut drag. When not in use, the fins are tucked into special grooves or depressions so that they lie flush with the body and do not break up its smooth contours. Airplanes retract their landing gear while in flight for the same reason. Tunas, mackerels, and billfishes have even more sophisticated adaptations than these to improve their hydrodynamics. The long bill of marlins, sailfishes, and swordfish probably helps them slip through the water. Many supersonic aircraft have a similar needle at the nose. 

    Most tunas and billfishes have a series of keels and finlets near the tail. Although most of their scales have been lost, tunas and mackerels retain a patch of coarse scales near the head called the corselet. The keels, finlets, and corselet help direct the flow of water over the body surface in such a way as to reduce resistance. Again, supersonic jets have similar features. 

     Because they are always swimming, tunas simply have to open their mouths and water is forced in and over their gills. Accordingly, they have lost most of the muscles that other fishes use to suck in water and push it past the gills. In fact, tunas must swim to breathe. They must also keep swimming to keep from sinking, since most have largely or completely lost the swim bladder, the gas-filled sac that helps most other fish remain buoyant. 

III. Insertion: 10% (Regardless of capitalization) 

Psychologists who study the learning process have observed that there are various distinct stages in cognition; memorization is 

one of the essential phases. While the acquisition of facts is almost utterly useless without the acquisition of conceptual knowledge 

and critical thinking skills, the latter cannot be practically taught without the former. 

It is a long-held 21_______ of faith among educators that the possession of a large vocabulary and a “head for names and 

dates” is only the most superficial sign of the mastery of a subject. 22_______ excellent mental calculators, people exceptionally 

skilled at performing mental arithmetic, have become notable mathematicians, because the practice of any academic field relies 

more heavily on conceptual thinking than raw computation of memorization ability. Thus, students who cram for tests by 

committing long lists of facts to 23_______ are unable to make use of those facts, to comprehend, analyze, synthesize, or 24_______ 

new ideas. Most educators would argue that these students could hardly be considered educated at all, in fact. 

The problem is, however, that ideas, trends, and concepts—the real substance of knowledge—cannot be acquired directly. At a 

young age, children are much better equipped to remember that 1776 was the year of the signing of the American Constitution than 

they are able to comprehend the founding fathers’ revolutionary politics. Only once young students acquire a certain store of raw 

facts can teachers 25_______ the process of posing challenging questions concerning the facts’ meanings. By 26_______ , one is 

much better equipped to analyze the meaning of a film after one has watched it, not 27_______ . In order to discuss the abstractions 

that form knowledge’s true substance, language requires that we first share a language of concrete terms through which we may 

communicate and form mutual judgments. 

It may be argued that what is most crucial is that teachers challenge their students to both acquire facts and analyze them at 

every stage of the learning process. The ability to memorize is best acquired at a young age, which is why education on many 

ancient civilizations consisted of the rote memorization of sacred texts. The learning curve of the memorization process does 28_______ 

off at a certain point. However, the development of analytic skills can increase exponentially 29_______ proper education. 

Memorization is like the infrastructure of a building—one must begin with it, but once it is built, the occupants of the building (the 

students) may expend as much energy as possible on making the building livable. 

Thus, the process of education, contrary to the claims of some purists, requires a certain degree of attention to the acquisition of 

facts. One cannot understand concepts without applying them 30_______ specific instances of knowledge, but, at the same time, 

education is not finished until one is taught to think about what one has memorized.

(A) for
(B) a great many
(C) memory
(D) with
(E) instigate (AB) article 

(AC) analogy (AD) during (AE) few (BC) emulate (BD) to (BE) taper