题目内容

The _____ of electricity added to our difficulty repairing the bridge.          

A. absence                  B. short                     C. need                     D. break

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Directions:Read the following three passages.Each passage is followed by several questions or unfinished statements.For each of them there are four choices marked A, B, C and D.Choose the one that fits best according to the information given in the passage.

  A rccent study of anclent and modern clcphants has come up with the uncxpeclcd conclusion that the african elcphant is dividcd into two disinct(不同的)species

  The discovery was made by researchers at yod and haycard yniwersities when they were examining the genetid relinship between the ancient woolly manmmth and mastodon to modern ckephants ins asoan alepnant a feoan forest elephant and afcican sannna clephant

  Once they obfantcd DNA sequences{序列}from two fossils{化石},mammothd and mastodons the team comparcd them with dna form ,modcrn eleohants they found to their amazement that modern forest and sabanna elephants are as distinct from cach other as asian elephants and manmoths he scientists used detailed genetic anatysis to proce that the african savanna clelhants hace been distinct species for several million years the divcrgonce of the ttwo species took place around the time of the of the dicergcncc of asian clephants and woolly mammoths this result amazed all the scienitsts

  There has long been debate in the scientific community that the two might be separespecies but this is the most convincing scientinfic evidence so far that they are anded difforent species

  Preci many naluralists believed that afrjcan savanna elephants and airican forest were two plpulations of the same apecies despite the clcphants signigice\ant sizw differences the sac\vanna elelphant has an average shouldcr height of 3.5metres while the forest slsphant has an average shouldcr height of 2.5metres the sacanna laphant welghs belween six anp secedn tons roughly double the weight of the forest elephant but the fact that they look so different does not neccssarily mean they are different species howecer the prooflay in the analysis of th DNA

  Alfred roca allisant professor in the dcoamment of animal scienccs at the unicerstiu of said “wu now nave to reat the forest and savanna elephants at two diffcrcnt units for consrrbation pucpooses since 1950 all african ele[hants are two cery distinctice animals the forest ele[hant shoule become a bigger prioity(优先)for conscrvation puruose”

(1)

one of the fossols studied by the reaearchers if that of ________

[  ]

A.

the asian elephant

B.

the forest elephant

C.

the savnna clcphant

D.

the maslodon elephant

(2)

the underlined word “divergence” in p[aragraph 4means “________”

[  ]

A.

evolution

B.

e\cxhibition

C.

separation

D.

cxamination

(3)

68.the resarchcrs conclusion was based on a study of the a frican elephant's ________

[  ]

A.

DNA

B.

height

C.

weight

D.

populalion

(4)

What are Alfred Roca's words mainly about?

[  ]

A.

The conservation of African elephants.

B.

The urose of studing African elephants.

C.

The way to divide African elephants into two units

D.

The reason for the distinction of African elephants.

(5)

Which of the following can be the best title for the passage?

[  ]

A.

Naturalists' Beliefs about Elephants

B.

Amazing Experiments baout Elephants

C.

An Unexpected Finding about Elephants

D.

A Long Scientific Debate baout Elephants

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