While the reading stresses three majoradvantages of genetically modified trees, the speech points out that if weinvestigate the three dimensions more closely, they will be no longer thatprominent.
The first advantage of genetic modification,according to the reading, is that it makes trees more resistant againstdetrimental environmental conditions. The speech argues, however, that lack ofgenetic diversity, caused by genetic modification, makes them vulnerableagainst problems that they are not designed for. Once an unexpected crisis isimposed on trees, naturally growing groups have higher chances of leavingsurvivors because these groups usually have at least some individuals that haveresistant genes(gene)against any arbitrary difficulty.
Higher economic return, which is claimed to be thesecond advantage of genetically modified trees, is contended by thespeaker to have been eaten up by higher price of seeds. Moreover, Farmers evenneed to pay every time they use those seeds for intellectual property right.Therefore, high yield of genetically modified trees does not really benefitfarmers.
As for the influence of genetically modified trees on other species, theopinion of the speaker is exactly the opposite from that of the writer. Thelatter asserts that modified trees are less harmful because higher yield pergeometric unit means they needs less space and resources to get the same returnthan naturally growing ones. The former refutes this assertion by saying thatmodified trees actually crowd out other species when they are planted together,which is likely the case.
语言不够精炼,独立也可以表现出来。大致简单了一些,主要多写听力,阅读一笔带过
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