Now many countries find themselves still struggling with problems that are as old as man h

ublic discourse and to avoid expressions that we might use in more casual situations. Among the features of formal English are the careful explanation of background information, complexity in sentence structure, explicit transitions between thoughts, and the use of certain words that are reserved chiefly for creating a formal tone. Situations that normally require formal usage would include an article discussing a serious matter submitted to a respected journal, an official report by a group of researchers to a government body, a talk presented to a professional organization, and a letter of job application.

止讨厌的男孩子打扰的武器。一位女孩儿说当她看到讨厌的男孩向她走来时，她最好的办法就是拿起手机假装与某人打电话。

数人选择坐火车的原因是省钱，费用相当于飞机的1/4。随着中国人生活水平不断提高，越来越多的人选择坐飞机，以节省时间。铁路主管部门一直在努力给客车加速，以增强竞争力。

r Major? " You should base your composition on the Chinese outline given below:

1．你认为在研究生学习阶段是选择一个好的学校重要还是选择一个好的专业重要?

2．你的理由是什么?

e. Consider a few statistics. Today, one out of every seven people in the world use English in some way. More than half the world's books are written in English; the majority of international telephone calls are made in English; 60% of the world's radio programs are broadcast in English. English is even the working language of international air travel. For the first time in history, a single language has become dominant across a wide range of human activity, ranging from music, film and fine arts to the fields of business, diplomacy, science and technology.

也就是说，中国每年丧失一个中等县面积的土地。当牲畜把见到的一切植被吃完时，表层土壤就会被刮走，只剩下沙子。沙尘暴的频发向我们发出警告：破坏大自然就等于自取灭亡。

ation. But as any experienced writer knows, there are occasions when even the best advice may not apply. The demands of writing for different audiences, with different purposes, on different subjects, at different levels of formality are so varied that they cannot begin to be anticipated in a book like this, and we recognize that what is appropriate for one piece of writing may not be appropriate for another. In most cases, you will have to avoid ambiguity at all costs so as not to leave your words open to misinterpretation.

的增加，雨林的面积在逐渐减少，直接威胁许多珍稀物种的生存。追求短期效益将导致长期的痛苦。保护生物多样性需要牺牲个人的利益。可惜的是相关国家政府并未达成共识。

取的可能性。但专家们指出，保持儿童对科学的好奇和兴趣有助于其智力发展。一个没有创造力和想象力的儿童很难有所作为。

方式因人而异。专家们一致认为经常运动、良好的饮食习惯和轻松的生活有助于长寿。