【正确答案】正确答案：Historical linguistics is a branch of linguistics concerned with examining changes in phonology, grammar, and semantics during a language"s evolution, reconstructing earlier stages, and uncovering evidence of the influence of other languages.(2 points) The purpose and significance of reconstruction is to recover the sound system, grammar, or lexicon of the protolanguage; (1)The identification of the changes enables us to reconstruct the linguistic history of that language, hypothesizes its earlier forms; (2)It enables us to determine how non-linguistic factors, such as social, cultural and psychological factors, interact over time to trigger linguistic change.(4 points) Historical linguists are concerned chiefly with establishing language families and reconstructing prehistoric proto-languages, using the comparative method and internal reconstruction. The comparative method compares languages with each other to establish their descent from a common ancestor. The comparisons are made in phonemes, morphemes, words, or syntactic constructions. Internal reconstruction is a method of recovering information about a language"s past from the characteristics of the language at a later date.(4 points)

【答案解析】解析：考查历史语言学。历史语言学是语言学的一个分支，它研究语言之间的亲属关系，关注对语言谱系的梳理和史前语言的测拟。一言以蔽之，其研究目的是观察语言变化；其研究方法主要是历史比较法和内在重构法。从其重要性方面来讲，因为历史语言学的研究目的是揭示语言变化的史前发展和同一语言早期和后期变体之间的联系，因此，它为不同语言之间的亲缘关系提供线索，此外，还可以使我们对非语言的因素，如社会文化和心理因素等在语言变化过程中所起的作用有更深的认识。