Historical Linguistics(历史语言学) is the study of language changes.

Anthropological linguistics(人文语言学) uses the theories and methods of anthropology to study language variation and language use in relation to the cultural patterns and beliefs of man.

Neurolinguistics(神经语言学) studies the neurological basis of language development and use in human beings.

Mathematical linguistics(数学语言学) studies the mathematical features of language, often employing models and concepts of mathematics.

Computational linguistics(计算语言学) is an approach to linguistics in which mathematical techniques and concepts are applied, often with the aid of a computer.

II. Phonetics(语音学）

1. scope of phonetics

Speech sounds may be studied from different angles, thus we have at least three branches of phonetics:

Articulatory phonetics(发音语音学）we may examine the way in which a speech sound is produced to discover which vocal organs are involved and how they coordinate(协调） in the process.

Auditory phonetics （听觉语音学）we may look into the impression a speaker makes on the hearer as mediated(调节） by the ear, the auditory nerve(神经） and the brain.

Acoustic phonetics (声学语音学） we study the physical properties of speech sounds, as transmitted（传送） between mouth and ear.

2. The vocal organs

The vocal organs may be viewed as consisting of three parts, the initiator of the air-stream,(气流发生器官） the producer of voice（声音发生器官） and the resonating cavities.（声音共振器官）

3. Consonants(辅音）

Places of articulation(发音部位）: bilabial,(双唇） Labiodentals,（唇齿） dental,（齿） alveolar,（齿龈） retroflex,（卷舌） palate-alveolar,（上齿龈）palatal,（上颚） velar,（软腭） uvular,（小舌） glottal(声门）

Manners of articulation: plosive,（暴破） nasal,（鼻音） trill,（颤音）lateral,（边音） fricative,（摩擦） approximant,（近似音） affricate（破擦）

4. Vowels (元音）

The classification of vowels: the height of tongue raising (high, mid, low), the position of the highest part of the tongue(front, central, back), and the degree of lip rounding(rounded, unrounded) III. Phonology（音韵学）

1. phonemes(音素）：a distinctive(有区别的） sound in a language.

2. Allophones(音位变体）：The nondistinctive sounds are members of the same phoneme.

3. Minimal pairs(最小对立体）： word forms which differ from each other only by one sound.

4. Free variation (自由变异）：If two sounds occurring in the same environment(环境）, they does not produce a different word form, but merely a different pronunciation of the same word.

5. Complementary distribution(补充分类）：Not all the speech sounds occur in the same environment. When two sounds never occur in the same environment.

6.Suprasegmental phonology(超音段音位）：the study of phonological properties(

性质） of units lager than the segment-phoneme. They are syllable(音节），stress,（重音） word stress, sentence stress. pitch （音调）and intonation（语调）.

IV. Morphology（词法）

1. inflection(构形法）：the grammatical relationships through the addition of inflectional affixes.(屈折词缀）

2. Word-formation(构词）：the processes(过程） of word variations signaling lexical relationships.（表明词法关系） They are compound(合成）and derivation (派生）.

3. Morpheme(词素）： the smallest unit in terms of relationship between expression and content.

4. Allomorph(同质异象变体）： some morphemes have considerable variation, for instance, alternate shapes or phonetic forms.

5. Types of morphemes: They are roots,(词根） affix（词缀） and stem（词干）.

6. Lexicon(语言词汇）：in its most general sense, is synonymous with vocabulary.

7. Closed-class words(封闭性） and open-class words(开放性）：the former whose membership is fixed or limited and the latter whose membership is in principle(实际上） indefinite or unlimited.

8. Word class(词性）：It displays a wider range of more precisely defined classes.

9. Lexeme(词位）：the smallest unit in the meaning system of a language that can be distinguished from other smaller units.

10. Idiom(习语，成语）：Most phrasal lexemes are idioms. It is especially true for a sequence of words(词序） which is semantically（语义上） and often syntactically(句法上） restricted.（限制）

11. Collocation(搭配）： the habitual(习惯的） co-occurrences （同时出现）of individual lexical items.

V. Syntax (句法）

1. Positional relation or word order（词序）：the sequential(顺序）arrangement of words in a language.