好的写作,首先是简洁,其次就要注意变化了,也就是标题所说的换种说法。因为许多考生易将简洁与简短混为一谈,其实二有很大区别。简洁的主旨是用尽量少的词汇讲述整个故事,简短的主旨则是为保持文章篇幅短小,精心撰写或随意删除文中的某些词语或章节。
简洁并不意味着总写短句子。事实上,如果句式缺乏变化,文章就会显得支离破碎,缺少联系,让人觉得写作技巧贫乏。句式的变化能令文章协调而流畅,会让读者感觉到作者对主题把握得游刃有余。虽然短句没什么语法错误,但用得太多会使本应合在一起的意思分离开来。
TIP:不要使用一串串短的、支离破碎的句子。要理清自己的思路,尽量使句子长度有所变化。 
例一
【原】The Art of Strategy was written by Sun Tzu’s. It is a fifty-six-hundred-word Chineseclassical work. The writer put forth a set of principles in a very tightly compressed manner. They deal with how to defeat oppositions and win battles.
这种表达的问题在于:
(1)简单的“主语+谓语”结构太多;
(2)"written"和"writer","TheArtofStrategy"和"It","setofprinciples"和"they"为重复用语;
(3)读起来很单调。
【改】In his fifty-six-hundred word classic, The Art of Strategy, Sun Tzu put forth a tightly compressed set of principles for achieving triumph over opposition.
介词结构+同位语+主语+谓语的形式比较好,因为将"SunTzu"放到了最重要成分-主语的位置,其他成分按逻辑排序居次要地位。整个句子很流畅。
例二
【原】Proverbs are short sayings. They are drawn from long experience.
【改】Proverbs are short sayings drawn from long experience.
例三
【原】People change and places change as well. Jennifer felt this strongly. She had been away for eleven years.
【改】On returning after an eleven-year absence, Jennifer had a strong feeling of how people and places change. 
例四
【原】Beijing streets are crowded with taxis, company cars and private vehicles owned by the newly affluent. The number has been rising rapidly in the last few years. The latest statistics show there are now 1.2 million vehicles in Beijing alone. 
【改】Taxis,companycarsandprivatevehiclesownedbythenewlyaffluenthavecrammed Beijingstreetsinrisingnumbersinthelastfewyears-1.2millionvehiclesatlastcount. 
例五
【原】Moby Dick is a book. It is a long book.It is about a whale.A man named Ahab tries to kill it. Her man Melville wrote it. 
【改】Her man Melville wrote a long book called Moby Dick. It is the story of a struggle of a man against a whale.
唯有多写多练,方能掌握更多的变化,同一个意思,n个表达方法,适当结合,就能形成一篇好的作文,18考研加油!