on steep mountain slopes. Similarly, alders have been planted to stabilize and rehabilitate waste material left over from old mines, flood deposits, and landslide areas in both Europe and Asia.
31. What does the passage mainly discuss?
(A)Differences between alder trees and Douglas fir trees
(B)Alder trees as a source of timber
(C)Management plans for using alder trees to improve soil
(D)The relation of alder trees to their forest environments
32. The word "dense" in line I is closest in meaning to
(A) dark
(B) tall
(C) thick
(D) broad
33. Alder trees can suppress the growth of nearby trees by depriving them of
(A) nitrogen
(B) sunlight
(C) soil nutrients
(D) water
34. Thc passage suggests that Douglas fir trees are
(A)a type of alder
(B)a type of evergreen
(C)similar to sword ferns
(D)fast-growing trees
35. It can be inferred from paragraph I that hemlock trees
(A) are similar in size to alder trees.
(B) interfere with the growth of Douglas fir trees
(C) reduce the number of alder trees In the forest
(D) need less sunlight than do Douglas fir trees
36. It can be inferred from paragraph 2 that previous generations of foresters
(A) did not study the effects of alders on forests
(B) did not want alders In forests
(C) harvested alders for lumber
(D) used alders to control the growth of evergreens
37. The word "they" in line 21 refers to
(A) newly developing soils
(B) alders
(C) bags
(D) chemical changes
38. According to the passage that alders are used in mountainous areas to
(A) nitrogen
(B) calcium
(C) carbon
(D) oxygen
39. It can be Inferred from the passage that alders are used in mountainous areas to
(A) prevent water from carrying away soil
(B) hold the snow
(C) protect mines
(D) provide material for housing
40. What is the author's main purpose in the passage?
(A) To argue that alder trees are useful in forest management
(B) To explain the life cycle of alder trees
(C) To criticize the way alders take over and eliminate forests
(D) To illustrate how alder trees control soil erosion
狗屎
Questions 41-50 In taking ups new life across the Atlantic, the early European settlers of the United States did not abandon the diversions with which their ancestors had traditionally relieved the tedium of life. Neither the harshness of existence on the new continent nor Line the scattered population nor the disapproval of the clergy discouraged the majority from the pursuit of pleasure.
City and country dwellers. of course. conducted this pursuit in different ways. Farm dwellers in their isolation not only found it harder to locate companions in play but also thanks to the unending demands and pressures of their work, felt it necessary to combine fun with purpose. No other set of colonists too so seriously on
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