TOEFL integrated writing: fuel-cell engines

The article states that the internal combustion engines should replace by fuel cell engine,because it includes a lot of advantages over internal combustion engine, and provides three reasons of support. However the professor explains that hydrogen is not suitable alternative source but she didn't deny the truth of what was said about burning oil, and she refutes each of the authors reasons.

First, the reading claims that the petroleum which the internal combustion depends on it is non renewable source, so it will finish after used it for long time. while hydrogen source can be produced from various sources. The professor refutes this point by saying that hydrogen is not easy available. She state that the hydrogen must obtain in pure liquid state which is a high artificial substance and it's very difficult to produce and restore it.

Second,the article posits that using hydrogen fuel cell will solve many pollution problems in compare with combustion engines. However, the professor says that using hydrogen will not solve the problem of pollution but it will increase it. According to the professor to get pure hydrogen it need a purification process that required a lot of energy produce by burning coal and oil, so the factories that will generate hydrogen will lead to increase the pollution problem.

Third, the reading says that using fuel-cell engine is more economic, since it needs less money to operate it in compare with combustion engine. The professor opposes this point by explaining that manufacturing of fuel cell engine is very expensive. We also learn that component of fuel cell engine is platinum which very rare and expensive,and we can't abandon on it, because without platinum the hydrogen doesnot undergo the chemical reaction that produce electricity to power automobile.

Votes
Average: 7 (4 votes)
Essay Categories

Sentence: However the professor explains that hydrogen is not suitable alternative source but she didn't deny the truth of what was said about burning oil, and she refutes each of the authors reasons.
Description: A noun, plural, common is not usually followed by a noun, plural, common
Suggestion: author's reasons

Sentence: She state that the hydrogen must obtain in pure liquid state which is a high artificial substance and it's very difficult to produce and restore it.
Description: The word state is not usually used as a verb, base: uninflected present, imperative or infinitive
Suggestion: Refer to state

Sentence: Second,the article posits that using hydrogen fuel cell will solve many pollution problems in compare with combustion engines.
Description: The token in is not usually followed by a verb, base: uninflected present, imperative or infinitive
Suggestion: Refer to in and compare

Sentence: According to the professor to get pure hydrogen it need a purification process that required a lot of energy produce by burning coal and oil, so the factories that will generate hydrogen will lead to increase the pollution problem.
Description: The fragment it need a is rare
Suggestion: Possible agreement error: Replace need with verb, past tense

Sentence: Third, the reading says that using fuel-cell engine is more economic, since it needs less money to operate it in compare with combustion engine.
Description: The token in is not usually followed by a verb, base: uninflected present, imperative or infinitive
Suggestion: Refer to in and compare

flaws:
No. of Grammatical Errors: 5 2

Don't need to reiterate the contents of reading passages or put only very little content.

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Attribute Value Ideal
Score: 22 in 30
Category: Good Excellent
No. of Grammatical Errors: 5 2
No. of Spelling Errors: 0 2
No. of Sentences: 11 10
No. of Words: 295 250
No. of Characters: 1492 1200
No. of Different Words: 149 150
Fourth Root of Number of Words: 4.144 4.3
Average Word Length: 5.058 4.6
Word Length SD: 2.507 2.4
No. of Words greater than 5 chars: 116 80
No. of Words greater than 6 chars: 96 60
No. of Words greater than 7 chars: 59 40
No. of Words greater than 8 chars: 32 20
Use of Passive Voice (%): 0 0
Avg. Sentence Length: 26.818 21.0
Sentence Length SD: 8.902 7.5
Use of Discourse Markers (%): 0.636 0.12
Sentence-Text Coherence: 0.412 0.35
Sentence-Para Coherence: 0.651 0.50
Sentence-Sentence Coherence: 0.162 0.07
Number of Paragraphs: 4 4