【正确答案】正确答案：Descriptive and Prescriptive are served as two different approaches in the linguistic study. Descriptive linguistics describes how a language is actually used. In other words, it focuses on the description and analysis of linguistic facts actually observed. Prescriptive linguistics tries to lay down rules for" correct language". The former is about what language is like and the latter is about what language should be like. For example, "A double-negative is used in our society" is a descriptive observation, while "You should never use a double-negative"is a prescriptive demand. Linguistics is defined as a scientific study of language. It is well known that language changes as the time passes by, so most contemporary linguists insist that whatever occurs naturally in the language should be described. To a certain extent, even if the rules imposed on a language function quite well at present, they are not necessarily correct in a longer term.

【答案解析】解析：考查描写式和规定式的区别。描写式和规定式是研究语言学的两种方式。描写式语言学指语言学家尽力去发现和记录语言的真实面貌，而规定式语言学则指语言学家制定了一些规则并且要求语言使用者遵守。语言学被定义为对语言的科学研究，而语言时刻处于发展变化之中，因此很多现代语言学家都认为这种发展和变化应该被如实地记录下来。