Starting in the 1960s and continuing until the 1980s, sailors in Russian submarines patrolling the North Atlantic and Arctic Ocean would occasionally hear strange sounds. These underwater noises reminded the submarine crews of frog croaks, so they called

Recently, some odd sounds, called quackers, were detected by Russian sailors in North Alantic and Artic Ocean. However, these sounds could not be distinguished by the sonar. In this case, the article proposes three possible theories about the origins of these sounds. However, none of these three theories are in favor by the professor since all of them are problematic from the viewpoints of professor.

First, the article suggests that quackers might be made from some special courtship rituals of Orca whales because males Orca whales usually use this kind of sounds, which is quite similar to these odd sounds detected by submarines, to attract the females. However, the professor points out that altought this theory of Orca seems to be possible, it is unlikely to happen. As the materials shown by the professor, the Orca whales live near the surface of the oceans while the submarines dive deeply into the seas to operte. Thus, these sounds could not be tracked by the sonars. What\'s more, this kind of whales are so massive that they could be seen by the detectors.

Then, the article states that this sounds would be produced by the giant squid, a kind of deep sea specie with soft body and no skeletons, which makes it quite difficult for sonars to detect it. But it\'s a tatally different case when it comes to the points of professor, the sounds of squids was first tracked by the sonars during 1960s. However, it has disappered since 1980s. Therefore, it would not be certain that why the squid appeared and disappear and it could not be the origin of the sounds.

Third, as the article shown, this sounds would be from some military technology of other country, which has not been registered in the sonars, making it unable to be detected. Nevertheless, as it described by the materials from the professor, the sounds moved around and changed its directions when being tracked. Therefore, it could not be the sounds of the submarines, because there would not be such a fast submarine without engine noises.

In a nutshell, the origin of these odd sounds are still unknown and it need more evidences.

Votes
Average: 7.6 (1 vote)
Essay Categories

Grammar and spelling errors:
Line 5, column 325, Rule ID: IN_1990s[1]
Message: The article is probably missing here: 'during the 1960s'.
Suggestion: during the 1960s
... squids was first tracked by the sonars during 1960s. However, it has disappered since 1980s...
^^^^^^^^^^^^

Transition Words or Phrases used:
but, first, however, if, nevertheless, so, still, then, therefore, third, thus, while, as to, kind of

Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments

Performance on Part of Speech:
To be verbs : 22.0 10.4613686534 210% => Less to be verbs wanted.
Auxiliary verbs: 11.0 5.04856512141 218% => Less auxiliary verb wanted.
Conjunction : 7.0 7.30242825607 96% => OK
Relative clauses : 10.0 12.0772626932 83% => OK
Pronoun: 32.0 22.412803532 143% => Less pronouns wanted
Preposition: 53.0 30.3222958057 175% => OK
Nominalization: 0.0 5.01324503311 0% => More nominalizations (nouns with a suffix like: tion ment ence ance) wanted.

Performance on vocabulary words:
No of characters: 1763.0 1373.03311258 128% => OK
No of words: 362.0 270.72406181 134% => OK
Chars per words: 4.87016574586 5.08290768461 96% => OK
Fourth root words length: 4.36191444098 4.04702891845 108% => OK
Word Length SD: 2.45289090441 2.5805825403 95% => OK
Unique words: 183.0 145.348785872 126% => OK
Unique words percentage: 0.505524861878 0.540411800872 94% => More unique words wanted or less content wanted.
syllable_count: 527.4 419.366225166 126% => OK
avg_syllables_per_word: 1.5 1.55342163355 97% => OK

A sentence (or a clause, phrase) starts by:
Pronoun: 8.0 3.25607064018 246% => Less pronouns wanted as sentence beginning.
Article: 9.0 8.23620309051 109% => OK
Subordination: 4.0 1.25165562914 320% => Less adverbial clause wanted.
Conjunction: 1.0 1.51434878587 66% => OK
Preposition: 3.0 2.5761589404 116% => OK

Performance on sentences:
How many sentences: 17.0 13.0662251656 130% => OK
Sentence length: 21.0 21.2450331126 99% => OK
Sentence length SD: 51.8714140796 49.2860985944 105% => OK
Chars per sentence: 103.705882353 110.228320801 94% => OK
Words per sentence: 21.2941176471 21.698381199 98% => OK
Discourse Markers: 5.94117647059 7.06452816374 84% => OK
Paragraphs: 5.0 4.09492273731 122% => OK
Language errors: 1.0 4.19205298013 24% => OK
Sentences with positive sentiment : 1.0 4.33554083885 23% => More positive sentences wanted.
Sentences with negative sentiment : 5.0 4.45695364238 112% => OK
Sentences with neutral sentiment: 11.0 4.27373068433 257% => Less facts, knowledge or examples wanted.
What are sentences with positive/Negative/neutral sentiment?

Coherence and Cohesion:
Essay topic to essay body coherence: 0.110025163611 0.272083759551 40% => OK
Sentence topic coherence: 0.0441512593052 0.0996497079465 44% => OK
Sentence topic coherence SD: 0.0385049950363 0.0662205650399 58% => OK
Paragraph topic coherence: 0.0659794855222 0.162205337803 41% => OK
Paragraph topic coherence SD: 0.0356685106351 0.0443174109184 80% => OK

Essay readability:
automated_readability_index: 12.2 13.3589403974 91% => Automated_readability_index is low.
flesch_reading_ease: 58.62 53.8541721854 109% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 10.3 11.0289183223 93% => OK
coleman_liau_index: 10.97 12.2367328918 90% => OK
dale_chall_readability_score: 8.12 8.42419426049 96% => OK
difficult_words: 79.0 63.6247240618 124% => OK
linsear_write_formula: 10.5 10.7273730684 98% => OK
gunning_fog: 10.4 10.498013245 99% => OK
text_standard: 11.0 11.2008830022 98% => OK
What are above readability scores?

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Rates: 76.6666666667 out of 100
Scores by essay e-grader: 23.0 Out of 30
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Note: the e-grader does NOT examine the meaning of words and ideas. VIP users will receive further evaluations by advanced module of e-grader and human graders.