this和that都可代表前面提到过的事情,若出现两个名词,指代前面的用that指代较后面的用this;但若指下文将要叙述事情,则只能用this,不能用that.此外,还可用于代替上文中出现过个单数或不可数名词,且后面带有of短语修饰.
　　Health is above wealth; this cannot give so much happiness as that.
　　健康胜于财富;财富不会像健康那样带来那么多幸福(句中this=wealth;that=health)
　　They cant afford it.That/this is their problem.
　　What I want you to remember is this :English is of great use.(此句中this不能用that替换)
　　The popula tion of Shanghai is larger than that of Suzhou.
而你给出的考题中,Partly that reflects the greater specialization~~~~这个句子仍然是与上文a few of the procedures or methods相关所要陈述的内容.这就运用了：若指下文将要叙述事情,则只能用this,不能用that.