(1) A fundamental term used in the phonetic classification of speech sounds, referring to the auditory result of the vibration of the vocal folds. Sounds produced while the vocal folds are vibrating are voiced sounds, e.g. [b, z, a, i]; those produced with no such vibration are voiceless or unvoiced, e.g. [p, s, h]. A sound which is normally voiced, but which in a particular phonetic environment is produced with less voice than elsewhere, or with no voice at all, is said to be devoiced (symbolized by a small circle beneath the symbol) - examples are the reduced voicing on voiced plosives in a word-final position as in bib, bed [bɪb], [bed].
(2) A category used in the grammatical description of sentence or clause structure, primarily with reference to verbs, to express the way sentences may alter the relationship between the subject and object of a verb, without changing the meaning of the sentence. The main distinction is between active and passive, as illustrated by The cat bit the dog and The dog was bitten by the cat: in the first sentence, the grammatical subject is the goal of the action - it is ‘acted upon’, and thus ‘passive’. There will be certain differences in the emphasis or style of these sentences, which will affect the speaker’s choice, but the factual content of the two sentences remains the same. In other languages, further contrasts in voice may be encountered, e.g. the ‘middle’ voice of Greek (which included verbs with a reflexive meaning, e.g. She cut herself), and there are several other types of construction whose role in language is related to that of voice, e.g. ‘reflexive’, causative, ‘impersonal’ constructions. Voice contrasts may be formally marked in the verb (e.g. by inflection, word-order or the use of special auxiliaries), or elsewhere in the sentence (e.g. by the use of passive ‘agent’); the English passive can involve all three factors, as in I was kicked by a bull.
（2）对句子或小句结构作语法描写的一个范畴，主要与动词相关，表达句子改变动词的主语和宾语之间的关系而又不改变句子意义的方式。“态”主要分主动态和被动态，例如The cat bit the dog“猫咬狗”和The dog was bitten by the cat“狗被猫咬”：前一句的语法主语同时是动作者；第二句的语法主语是动作的目标，是“动作的对象”，因此是“被动的”。这两个句子在强调重点和风格上有所差别，这会影响说话人的选择，但在事实内容上两个句子相同。其他语言中还可能见到其他的态，例如希腊语有“中间”态（包括带反身意义的动词，如She cut herself“她割她自己”），而且有多种其他构式在语言中的作用跟这种形态有关，例如“反身式”、使役式、“无人称”构式等。态的对立可由动词带形式标记表示（例如屈折形式，词序或使用特殊的助动词），也可由句子其他部分表示（例如用被动“施事”）；英语被动态可能同时涉及上述三个因素，如I was kicked by a bull“我被一头公牛踢了一脚”。