51.Unfortunately, however, with the growing prosperity of Chinese economy, quite a number of rich people are choosing to live in luxuries, sometimes to the point of extravagance。

　　52.It is widely recognized (generally accepted) that extensive deforestation contributed to heavy summer flooding。

　　53.It is reported that 800000 applicants sat for the National Master’s Entrance Test in 2003。

　　54.It must be admitted that the price war will disturb the normal order of the market。

　　55.It cannot be denied that the overgrowth of tourism may destroy the ecological balance of some scenic resorts。

　　56.It is known to all that physical exercises can improve and enrich our physical and mental well-being。

　　57.It is estimated that over 800,000 Chinese have moved to and settled down in the US in the past 150 years。

　　58.It is obvious /evident /clear /apparent that the situation is caused directly by excessive commercial fishing。

　　59.It is understandable (inevitable) that people’s attitudes are divergent on this controversial issue。

　　60.It is unimaginable (incredible/unbelievable) that such a boy of 17 should have had three novels published。

　　51。然而，不幸的是，随着中国经济的持续繁荣，许多富裕的人们选择了奢侈生活，乃至有时浪费。

　　52。众所周知，大量地砍伐森林会导致夏天洪水泛滥。

　　53。据报道，2003年有800000考生申请参加硕士研究生入学考试。

　　54。必须承认，价格战会扰乱市场秩序。

　　55。不可否认，旅游业的过快增长会破坏风景名胜地的生态平衡。

　　56。众所周知，体育锻炼提高并丰富我们的身心健康。

　　57。据估计，过去的150年中，有800000多万的中国人移居美国。

　　58。显然，事态是由过分的商业捕捞直接造成的。

　　59。可以理解的是/不可避免的是，人们在这个有争议的问题上的态度是不尽相同的。

　　60。难以想象的是/难以置信的是，一个17岁的孩子已经出版了三本小说。