Some people believe there should be single international language. Others believe that would make it difficult to maintain the identity of cultures. Discuss both these views and give your own opinion.
In the past, several languages have acted as the lingua franca in different areas of the world, but the growth of modern communications and the development of air transport have created a demand for a single international language to cover the whole world.(第一段没有任何模板痕迹，用自己的语言描述问题背景。用到了lingua franca 替换 single international language 体现了考生的词汇量。第一段只有一句话，简洁，明了。)
There are several reasons supporting that a single international language has become a practical necessity.（第二段讨论第一个观点：需要一个世界语言。主题句用到supporting非谓语体现语法多样性） Firstly, trade is becoming increasingly international, involving multiple partners who have mutually incomprehensible mother tongues. Secondly, there has been a huge proliferation of international organisations, such as UNICEF, the WHO and the European Union（举例）. Thirdly, scientific research, such as space and genetic research, is becoming more of an international cooperative effort. Although multi-way translation is technically available and sometimes practised, it is often expensive and inconvenient. Fourthly, it is arguable that if we all make use of one language to communicate, prejudice and misunderstandings will be overcome and world peace will be promoted.（一二三四条理清晰，用到了举例论证，对比论证）
Many people fear that the spread of a single international language threatens individual cultures.（第三段讨论第二个观点） It is argued, for example, that the spread of one language will cause others to die out. However, there is evidence to the contrary. History suggests that the use of one or more official languages has in fact sharpened the sensitivity of speakers to other languages. More broadly, people fear that a single language will spread a single culture over the world, a movement sometimes called “language colonisation”. But we should keep in mind that the purpose of an international language is for use in international contexts, not everyday ones. Any international language is likely to remain superficial. （地道词汇需要大家背诵积累）
Therefore, my conclusion is that the enormous benefits of a single international language vastly outweigh the potential risks it presents. (最后一段总结全文，表明自己的观点。)