单选题
Legend has it that sometime toward the Civil War
(1861～1865) a government train carrying oxen traveling through the northern
plains of eastern Wyoming was caught in a snowstorm and had to be abandoned. The
driver returned the next spring to see what had become of his cargo. Instead of
the skeletons he had expected to find, he saw his oxen, living, fat and healthy.
How had they survived? The answer lay in a resource that
unknowing Americans had trampled underfoot in their haste to cross the "Great
American Desert" to reach lands that sometimes proved barren. In the eastern
parts of the United States, the preferred grass for forage was as cultivated
plant. It grew well with enough rain, then when cut and stored it would cure and
become nourishing hay for winter feed. But in the dry grazing lands of the west,
that familiar blue joint grass was often killed by drought. To raise cattle out
there seemed risky or even hopeless. Who could imagine a fairy
tale grass that required no rain and somehow made it possible for cattle to feed
themselves all winter? But the surprising western wild grasses did just that.
They had wonderfully convenient features that made them superior to the
cultivated eastern grasses. Variously known as buffalo, grama grass, or mesquite
grass, not only were they immune to drought; but they were actually preserved by
the lack of summer and autumn rains. They were not juicy like the cultivated
eastern grasses, but had short, hard stems. And they did not need to be cured in
a barn, but dried right where they grew on the ground. When they dried in this
way, they remained naturally sweet and nourishing through the winter. Cattle
were left outdoors to fend for themselves thrived on this hay. And the cattle
themselves helped plant the fresh grass year after year, for they trampled the
natural seeds firmly into the soil to be watered by the melting snows of winter
and the occasional rains of spring. The dry summer air cured them, much as
storing in a barn cured the cultivated grasses.
单选题
What does the passage mainly discuss?
A. Western migration after the Civil War.
B. The raising of cattle.
C. A type of wild vegetation.
D. The climate of the western United States.
【正确答案】
C
【答案解析】[解析] 本文主要是介绍一种野生植物。
单选题
Which of the following can be inferred about the cultivated grass
mentioned in Para.2?
A. It had to be imported into the United States.
B. Cattle raised in the western United States refused to eat it.
C. It was difficult for cattle to digest.
D. It would probably not grow in the western United States.
【正确答案】
D
【答案解析】[解析] 文中有“In the eastern parts of the United States, the preferred grass for forage was as cultivated plant”。
单选题
Which of the following was NOT one of the names given to the western
grasses?
A. Buffalo grass.
B. Blue joint grass.
C. Mesquite grass.
D. Grama grass.
【正确答案】
B
【答案解析】[解析] 文中第三段有“Variously known as buffalo, grama grass, or mesquite grass...”。
单选题
Which of the following was NOT mentioned as a characteristic of the
western grasses?
A. They are not affected by dry weather.
B. They contain little moisture.
C. They have tough stems.
D. They can be grown indoors.
【正确答案】
D
【答案解析】[解析] 文中并未提及这种植物能在室内种植。
单选题
According to the passage, the cattle helped promote the growth of the
wild grasses by ______.
A. continually moving from one grazing area to another
B. naturally fertilizing the soil
C. eating only quantities of grass
D. stepping on and pressing the seeds into the ground