Phonetics is the study of the phonic medium of language; it is concerned wiht all the sounds that occur in the world's langues.
Three Branches
Articulatory phonetics
：发音语言学
concerns the production产生, description描述 and classification 分类of speech sounds.
Auditory phonetics：听觉语言学
concerns how the sounds are perceived（感知） by the hearer
Acoustic phonetics:声学语言学
concerns the physical means by which sounds are transmitted through the air from one person to another.
2 Organs of speech：发音器官
The pharyngeal cavity：咽腔
voicing:浊化
voiceless:清音
The oral cavity：口腔
The nasal cavity：鼻腔
3 Representation of speech sounds (IPA)
The basic principle of the IPA is using one letter selected from major European languages to represent one speech sound.
broad transcription：宽式标音
The transcription with letter-symbols
narrow transcription：严式标音
The transcription with letter-symbols together with the diacrities（变音符）
4Classification of English speech sounds（语音）
Voiceless（清音）: the vocal folds are apart, the air can pass through easily and the sound produced is said to be voiceless. [p, s, t]
Voiced（浊音） : when the vocal folds(声带 )are close together, the airstream causes them to vibrate against each other and the resultant sound is said to be voiced. [b, z, d]气流相互震动产生浊音.
Consonants（辅音）:produced by obstructing air stream in the process of articulation在发音过程中阻塞气流产生的.
Classification
Manner of articulation（发音方式）: the actual relationship between the articulators（发音器） and thus the way in which the air passes through certain parts of the vocal tract（声道）.
aim to discover how speech sounds（语音） in a language form patterns(形成模式) and how these sounds are used to convey meaning (表达意义 )in linguistic communication.
2.2. phone, phoneme, and allophone
Phone（音素）: a phonetic unit语言单位. It is the speech sounds we hear and produce during linguistic communication.
Phoneme（音位）: a phonological unit音位学单位. It is the smallest unit of sound that can distinguish meaning有区别意义. It is an abstract unit and not any particular sound.
Allophones(音体变位）:the different phones which can represent a phoneme in different phonetic environments are called the allophonesof that phoneme.在不同的语音环境下代表某个音位的音素被称为该音位的音位变体。
e.g. the /p/ sound in speak and peak. The /p/ in the first word is unaspirated不送气的, it is transcribed as [ p= ]; the /p/ in the second word is aspirated送气的, and is transcribed as [ ph ].
2.3 phonemic contrast（音位对立), complementary
distribution(互补分布）, and minimal pair（最小对立体）
Minimal pairs: a technique which is used to find out which sound substitution causes differences of meaning
Phonemic contrast: different phonemes
Complementary distribution: allophones of the same phoneme.
e.g. [l] [l]
2.4 some rules in phonology
Sequential rules(序列规则):Rules that govern the combination of sounds in a particular language are called sequential rules.
Assimilation同化
definition:a process by which one sound takes on some or all the characteristics of a neighboring sound.
