8-11 综合 In the lecture, the professor comments that though the passage is right in pointing out that the energy recourses the internal-combustion engine relies on are finite and that operating the internal-combustion engine pose great harm to the environment; it exaggerates the role of hydrogen engines in solving all these defects concerned. Then she goes further illustrating in three parts.
Firstly, the recourses are not so available and practical to extract as the passage indicates. Despite the availability of water, it could not be directly used by hydrogen-based fuel cells. It requires pure liquid state hydrogen which is technically difficult to store, thus refutes the first advantage held in the passage that the resources fuel-cell engines utilize are easily available and renewable.
In addition, the fuel-cells are impotent in effectively solve the car problems mentioned. Considering its production requires purification process which result in large quantity of coal and oil-burning, the fuel-cells are not that much environmentally-friendly as assumed, which renders the second advantage less charming.
Finally, the adoption of the fuel-cell is no better cost-saving than the internal-combustion engine. The fuel-cells require a rare metal to participate in the production process and add a lot to the cost. This contradicts the third advantage held by the passage.
In a nut shell, the professor points out several defects the passage fail to take into consideration.
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