可汗SAT语法48篇：Classifying the Stars!SAT备考中考生使用比较广泛的复习资料包括官方指南OG和可汗学院SAT系列资料。下面智课网为大家整理了可汗SAT语法48篇中Classifying the Stars的内容，供大家练习。

Questions 1-5 are based on the following passage.

Classifying the Stars

In astronomy, stellar classification is governed by　the Morgan-Keenen system, which categorizes stars　based on their composition and surface temperature. The　origins of this system can be traced back to the work of　Annie Jump Cannon, a late nineteenth-century and early　twentieth-century ①astronomer. Spending over forty　years classifying stars based on their unique spectra of　transmitted light.

[1] Beginning early in her life, Cannon demonstrated　an exceptional aptitude for the physical sciences. [2]　Later, as a student at Wellesley College, Cannon earned a　degree in physics and became an expert in spectroscopy:　the process by which light is separated into its component　wavelengths. [3] During this period, she also took up photography and traveled extensively in order to experiment with the newly invented black-box camera.　[4] As a child, she developed an interest in astronomy and　purportedly used her attic as a makeshift observatory. ②

Cannon‘s background in physics, astronomy, and photography provided her with a unique skillset that ③ will serve her well for the rest of her career. After working as a research assistant for a number of astronomers at Wellesley and Radcliffe Colleges, Cannon was hired by Professor Edward Charles Pickering, the director of the Harvard College Observatory. Under Pickering, she classified over 300,000 stars-more than any other human in history-using only a telescope, a spectrometer, and a camera. Using this knowledge, she developed her own classification system that relied on the surface temperature of the stars, which could be approximated using the spectrum of light transmitted from each star. It was said that Cannon could classify three stars a minute and, using a magnifying glass, could classify stars down to the 9th magnitude-sixteen times fainter than ④ humans. Today, Cannon‘s unique classification system is used by countless astronomy enthusiasts around the world.

⑤ Pickering was succeeded by Harlow Shapley.Shapley once said that Cannon's contribution to astronomy was “a structure that probably will never be duplicated in kind or extent by a single individual.” Indeed, Cannon‘s work has forever shaped our comprehension and perception of the vast and elaborate universe.

1

A) NO CHANGE

B) astronomer, she spent

C) astronomer spent

D) astronomer who spent

2

To make the paragraph most logical, sentence 4 should be placed

A) where it is now.

B) before sentence 1.

C) after sentence 1.

D) after sentence 2.

3

A) NO CHANGE

B) serve

C) would serve

D) has served

4

A) NO CHANGE

B) the human eye.

C) that of the human eye.

D) what can be seen by the human eye.

5

Which choice most effectively combines the underlined sentences?

A) Harlow Shapley, who once said Cannon‘s contribution to astronomy was ―a structure that probably will never be duplicated in kind or extent by a single individual," was Pickering‘s successor.

B) Pickering was succeeded by Harlow Shapley, and Shapley once said that Cannon‘s contribution to astronomy was ―a structure that probably will never be duplicated in kind or extent by a single individual."

C) ―A structure that probably will never be duplicated in kind or extent by a single individual" was once said by Pickering‘s successor, Harlow Shapley, about Cannon‘s contribution to astronomy.

D) Harlow Shapley, the astronomer who succeeded Pickering, once referred to Cannon‘s contribution to astronomy as ―a structure that probably

will never be duplicated in kind or extent by a

single individual."