The word "heart" is closest in meaning to which of following?
(A) center
(B) edge
(C) tail
(D) beginning
402. The most graphic proof that the grand spectacle of a comet develops from a relatively small and inconspicuous chunk of ice and dust was the close-up image obtained in 1986 by the European Giotto probe of the nucleus of Halley's Comet.
The word "graphic" is closest in meaning to which of following?
(A) mathematical
(B) popular
(C) unusual
(D) vivid
403. As a comet's orbit brings it closer to the Sun, first the coma grows, then two distinct tails usually form.
The word "distinct" is closest in meaning to which of following?
(A) visible
(B) gaseous
(C) separate
(D) new
404. Pheromones are substances that serve as chemical signals between members of the same species.
The word "serve" is closest in meaning to which of following?
(A) improve
(B) function
(C) begin
(D) rely
405. Pheromones are the predominant medium of communication among insects (but rarely the sole method) . Some species have simple pheromone systems and produce only a few pheromones, but others produce many with various functions.
The word "sole" is closest in meaning to which of following?
(A) obvious
(B) best
(C) only
(D) final
406. Some species, such as ants, seem to be very articulate creatures, but their medium of communication is difficult for humans to study and appreciate because of our own olfactory insensitivity and the technological difficulties in detecting and analyzing there pheromones.
The word " detecting " is closest in meaning to which of following?
(A) controlling
(B) storing
(C) questioning
(D) finding
407. Aphids, which are particularly vulnerable to predators because of their gregarious habits and sedentary nature, secrete an alarm pheromone when attacked that causes nearby aphids to respond by moving away.
The word "sedentary" is closest in meaning to which of following?
(A) inactive
(B) inefficient
(C) unchangeable
(D) unbalanced
408. These innovations in manufacturing boosted output and living standards to an unprecedented extent;the average per capita wealth increased by nearly 1 percent per year-30 percent over the course of a generation.
The word "boosted" is closest in meaning to which of following?
(A) ensured
(B) raised
(C) arranged
(D) discouraged
409. Since the 1790's, North American entrepreneurs --- even without technological improvements --- had broadened the scope of the outwork system that made manufacturing more efficient by distributing materials to a succession of workers who each performed a single step of the production process.
The word "scope" is closest in meaning to which of following?
(A) value
(B) popularity
(C) extent
(D) diversity
410. As early as 1782 the prolific Delaware inventor Oliver Evans had built a highly automated, laborsaving flour mill driven by water power.
The word "prolific" is closest in meaning to which of following?
(A) efficient
(B) productive
(C) self-employed
(D) progressive
参考答案：A D C B C D A B C B
