http://s7/mw690/001JtQgrzy6OpZPH60ma6&690The Lewis and Clark expedition" TITLE="[老托福阅读9] The Lewis and Clark expedition" />



The Lewis and Clark expedition, sponsored by President Jefferson, was the most important official examination of the high plains and the Northwest before the War of 1812. The President's secretary, Captain Meriwether Lewis, had been instructed to "explore the Missouri River, and such principal streams of it as, by its course and communication with the waters of the Pacific Ocean …may offer her most direct and practicable water communication across the continent, for the purposes of commerce." Captain William Clark, the younger brother of famed George Rogers Clerk, was invited to share the command of the exploring party.

  Amid rumors that there were prehistoric mammoths wandering around the unknown region and that somewhere in its wilds was a mountain of rock salt 80 by 45 miles in extent, the two captains set out. The date was May 14, 1804. Their point of departure was the mouth of the Wood River, just across the Mississippi from the entrance of the Missouri River. After toiling up the Missouri all summer, the group wintered near the Mandan villages in the center of what is now North Dakota. Resuming their journey in the spring of 1805, the men worked their way along the Missouri to its source and then crossed the mountains of western Montana and Idaho. Picking up a tributary of the Columbia River, they continued westward until they reached the Pacific Ocean, where they stayed until the following spring.

  Lewis and Clark brought back much new information, including the knowledge that the continent was wider than originally supposed. More specifically, they learned a good deal about river drainages and mountain barriers. They ended speculation that an easy coast-to-coast route existed via the Missouri-Columbia River systems, and their reports of the climate, the animals and birds, the trees and plants, and the Indians of the West – though not immediately published – were made available to scientists.

More information: The Lewis and Clark expedition




34. With what topic is the passage primarily concerned?
(A) The river systems of portions of North America.
(B) Certain geological features to the North American continent.
(C) An exploratory trip sponsored by the United States government.
(D) The discovery of natural resources in the United States.

35. According to the passage, the primary purpose of finding a water route across the continent was to
(A) gain easy access to the gold and other riches of the Northwest
(B) become acquainted with the inhabitants of the West.
(C) investigate the possibility of improved farmland in the West.
(D) facilitate the movement of commerce across the continent

36. The river Meriwether Lewis was instructed to explore was the
(A) Wood
(B) Missouri
(C) Columbia
(D) Mississippi

37. According to the passage, the explorers spent their first winter in what would become
(A) North Dakota
(B) Missouri
(C) Montana
(D) Idaho

38. The author states that Lewis and Clark studied all of the following characteristics of the explored territories EXCEPT
(A) mineral deposits
(B) the weather
(C) animal life
(D) native vegetation

39. The phrase "Picking up" in line 13 could best be replaced by which of the following?
(A) Searching for
(B) Following
(C) Learning about
(D) Lifting

40. It can be inferred from the passage that prior to the Lewis and Clark expedition the size of the continent had been
(A) of little interest
(B) underestimated
(C) known to native inhabitants of the West
(D) unpublished but known to most scientists

41. Where in the passage does the author refer to the explorers' failure to find an easy passageway to the western part of the continent?
(A) Lines1-2
(B) Lines4-5
(C) Lines9-11
(D) Lines12-14