本文的内容就是【加氟自来水】，综合写作的运用，还要锻炼短时间迅速了解阅读、听力材料中的要点以及相应例证的能力。下面通过对具体题目进行分析，希望可以帮助到你们。
加氟自来水(adding fluoride in public water)
reading
在自来水中加氟的好处
1.防止蛀牙
2.杀死细菌
3.对骨骼有好处(decrease bone diseases)
lecture
反驳
1.自来水并不会留在口中，对防止蛀牙没有帮助
2.氟会与输水管(water pipe)中的化学物质反应，产生有毒物质，其危害大于细菌
3.过量的氟会使骨骼变脆
例文：The speaker refutes the reading's argument about the benefits of adding fluoride to pipe water by providing contradictory evidence about pipe water's fluoride's effectiveness in preventing cavities in teeth, killing bacteria, and decreasing bone diseases.
First, the speaker points out that the short contact of fluoride with teeth will not enable the fluoride to prevent cavities, as the reading argues. Instead, the water will pass the mouth and teeth quickly and go directly to the stomach.
Another argument raised in the lecture is that fluoride could undergo chemical reactions with heavy metals in the pipe, such as lead. This will create toxic substances which will pose serious health threat. In this way fluoride could be even more deadly than bacteria. Although the fluoride, as the reading says, will kill some bacteria, the cure here is worse than the disease.
In the end, the speaker maintains that overdose of fluoride will backfire to human bones. Although the reading illustrates that fluoride will improve bone strength, the lecture says overdose will cause serious damage to human bones.
以上的内容是托福综合写作范文【加氟自来水】，希望可以帮助大家提升