多看范文对自己写作水平的有好处，正所谓集思广益才能不断。下面跟着北京新航道托福频道去看一篇TPO9综合写作范文吧，希望大家对照范文，总结经验教训，自己的写作水平。

　　TPO 9

　　The lecturer points out several problems with the use of hydrogen-based fuel-cell engines in support of her claim that substituting them for internal-combustion engines is technologically unfeasible, environmentally unfriendly, and economically unviable.

　　First, the lecturer states that it is impractical to replace internal-combustion engines with fuel-cell engines because using the latter requires hydrogen in a pure liquid form, which is technologically challenging to both obtain and store. However, the reading argues that because hydrogen can be extracted from many resources including water, fuel cell engines powered by this infinite source of energy are an extremely attractive alternative.来源：北京新航道托福培训

　　Second, the lecturer refutes the claim in the reading that hydrogen cells are environmentally friendly. She argues that although engines that use hydrogen cells produce less pollution, the manufacturing of hydrogen cells generates large amounts of harmful by-products due to the burning of fossil fuels in the purification process.

　　Third, although the reading suggests that hydrogen-based engines are more fuel-efficient and thus economically competitive than internal-combustion engines, the professor argues that such an advantage is undermined by the fact that fuel-cell engines are extremely expensive to manufacture because they require the addition of platinum, a very rare and expensive material.

　　上面就是托福TPO8综合写作范文，考生对照题目和范文认真做练习，手机资料备考，争取考试取得好成绩，加油!

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