Integrated test
The sea otter is a small mammal that lives in waters along the western coast of North America from California to Alaska. When some sea otter populations off the Alaskan coast started rapidly declining a few years ago, it caused much concern because sea otters play an important ecological role in the coastal ecosystem. Experts started investigating the cause of the decline and quickly realized that there were two possible explanations: environmental pollution or attacks by predators. Initially, the pollution hypothesis seemed the more likely of the two.
The first reason why pollution seemed the more likely cause was that there were known sources of it along the Alaskan coast, such as oil rigs and other sources of industrial chemical pollution. Water samples from the area revealed increased levels of chemicals that could decrease the otters' resistance to life-threatening infections and thus could indirectly cause their deaths.
Second, other sea mammals such as seals and sea lions along the Alaskan coast were also declining, indicating that whatever had endangered the otters was affecting other sea mammals as well. This fact again pointed to environmental pollution, since it usually affects the entire ecosystem rather than a single species. Only widely occurring predators, such as the orca (a large predatory whale), could have the same effect, but orcas prefer to hunt much larger prey, such as other whales.
Third, scientists believed that the pollution hypothesis could also explain the uneven pattern of otter decline: at some Alaskan locations the otter populations declined greatly, while at others they remained stable. Some experts explained these observations by suggesting that ocean currents or other environmental factors may have created uneven concentrations of pollutants along the coast.
The speaker refute the conclusion that the decrease of number of see otters is caused by pollution, mainly by three points contrary to the three reasons stated in the passage.
First, even though the pollution hypothesis is possible, there are no dead sea otters found off shore, which worsen the hypothesis that the bodies may be found near land or even on beaches if otters died becouse of pollution and the resulting decrease of resistance to life-threatening factors. On the contrary, if the major couse of this decline is the attacks by predators, the dead sea ottors will be deep in the sea a...
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Sentence: The speaker refute the conclusion that the decrease of number of see otters is caused by pollution, mainly by three points contrary to the three reasons stated in the passage.
Description: The fragment speaker refute the is rare
Suggestion: Possible agreement error: Replace refute with verb, past tense
Sentence: First, even though the pollution hypothesis is possible, there are no dead sea otters found off shore, which worsen the hypothesis that the bodies may be found near land or even on beaches if otters died becouse of pollution and the resulting decrease of resistance to life-threatening factors.
Error: becouse Suggestion: because
Sentence: On the contrary, if the major couse of this decline is the attacks by predators, the dead sea ottors will be deep in the sea and not washed off shore, coinciding with the observation.
Error: couse Suggestion: cause
Sentence: Third, while some scientists believed the pollution hypothesis could also describe the uneven patten of otter decline, the predator one can explain it to a very good extent.
Error: patten Suggestion: pattern
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Attribute Value Ideal
Score: 28 in 30
Category: Excellent Excellent
No. of Grammatical Errors: 1 2
No. of Spelling Errors: 3 2
No. of Sentences: 11 10
No. of Words: 272 250
No. of Characters: 1282 1200
No. of Different Words: 152 120
Fourth Root of Number of Words: 4.061 4.7
Average Word Length: 4.713 4.6
Word Length SD: 2.326 2.4
No. of Words greater than 5 chars: 93 80
No. of Words greater than 6 chars: 53 60
No. of Words greater than 7 chars: 33 40
No. of Words greater than 8 chars: 20 20
Use of Passive Voice (%): 0 0
Avg. Sentence Length: 24.727 21.0
Sentence Length SD: 10.296 7.5
Use of Discourse Markers (%): 0.818 0.12
Sentence-Text Coherence: 0.368 0.35
Sentence-Para Coherence: 0.616 0.50
Sentence-Sentence Coherence: 0.092 0.07
Number of Paragraphs: 4 4