The main task in this section is to identify phonemes,i.e. to judge whether two or more sounds are separate phonemes or different allophones of the same phoneme. For example:
本節的主要任務是識別音位，即判斷兩個或兩個以上的聲音是獨立的音位還是同一音位的不同音位變體。例如:
Before we discuss how to judge whether two given sounds are different phonemes or not, it's necessary for us to give a brief introduction to the three types of distribution, which are indispensable to the job of identifying phonemes.
在我們討論如何判斷兩個給定的聲音是否是不同的音位之前，有必要先簡單介紹一下三種類型的分布，這是識別音素必不可少的工作。
一、 contrastive distribution，complementary distribution and free variation 對比分布，互補分布和自由變異
The distribution of a sound refers to the collective environments in which the sound concerned may appear.
一個聲音的分布是指其有關的聲音可能出現的集體環境。
Bussmann has a comprehensive classification of distribution.
德國語言學家布斯曼有一個全面的分布分類
In the following parts,we shall introduce three major types of distribution, by means of which we can describe the relationship between two or more sounds.
在接下來的部分，我們將介紹三種主要的分布類型，通過它們我們可以描述兩種或更多的聲音之間的關係。
They are contrastive distribution, complementary distribution and free variation.它們分別是對比分布、互補分布和自由變異。
1）contrastive distribution對比分布
If two or more sounds can occur in the same environment and the substitution of one sound for another brings about a change of meaning，they are said to be in contrastive distribution.
如果兩個或更多的聲音可以發生在相同的環境並且一旦一個聲音替換另一個會改變的意思,那他們就是處於對比分布。
Obviously,the different sounds involved in a minimal pair, such as [m] in met and [n] in net are in contrastive distribution because substituting [m] for [n] will result in a change of meaning.
顯然，最小對立體中包含的不同聲音，如met中的[m]和net中的[n]是處於對比分布的，因為用[m]代替[n]會導致意義的改變。
It's the same case with [p] and [k]in words spill and skill.
[p]和[k]在單詞spill 和 skill方面也是如此。
2）complementary distribution互補分布
If two or more sounds never appear in the same environment，that is，each sound only appears in the environments where the other sound never occurs，then they are said to be in complementary distribution.
如果兩個或更多的聲音從未出現在相同的環境中,也就是每一個聲音只出現在其他的聲音不出現的環境中,然後他們被稱為處在互補分布。
For example, the aspirated plosive [ph] and the unaspirated plosive [p] are in complementary distribution because the former occurs either initially in a word or initially in a stressed syllable while the latter never occurs in such environments.
例如，送氣爆破音[ph]和非送氣爆破音[p]是處於互補分布，
因為前者[ph]要麼出現在一個單詞的開頭或一個重讀音節的開頭，而後者[p]從未出現在這樣的環境中。
The allophones of the same phoneme are usually in complementary distribution.
同一音位的音位變體通常是處於互補分布的。
More examples can be found in the relation between an oral vowel and its corresponding nasal vowel, between a clear lateral liquid and its corresponding dark sound, between a bilabial nasal and a labiodental nasal,and so on.
更多的例子可以在口腔元音和它相應的鼻元音之間，在清晰的旁流音和它相應的dark sound之間，在雙唇鼻音和唇齒鼻音之間等等的關係中找到。
3）free variation 自由變異
When two sounds can appear in the same environment and the substitution of one for the other does not cause any change in meaning，they are said to be in free variation.
當兩個聲音可以出現在相同環境但是替換一個其他不會導致任何意思的改變, 然後他們被稱為處在自由變異。
In this case, the substitution only causes a change in pronunciation of the same word.
在這種情況下，替換隻會導致同一單詞的發音發生變化。
For example, in English, the word direct may be pronounced in two ways:
例如，在英語中，direct這個詞有兩種發音方式:
/direkt/ and /dairekt/, and the two different sounds/i/ and /ai/ can be said to be in free variation.
/direkt/ and /dairekt/, 而/i/和/ai/這兩種不同的聲音可以說是處於自由變異的。
It's the same case with ask, dance, economics, neither, either, etc.
這和ask, dance, economics, neither, either等的情況是一樣的。
二、Principles of identifying phonemes 識別音位的四個原則
To determine whether two sounds are separate phonemes or allophones of the same phoneme, we need to check the following four principles:
要判斷兩個音是獨立的音位還是同一音位的不同音位變體，我們需要核對以下四個原則:
(1)If two sounds are found to be in contrastive distribution, then they are said to be separate phonemes.如果發現兩個音處於對比分布，則稱它們為獨立的音位。
(2)If there exist two sounds which are always in free variation, then they are regarded as two allophones of the same phoneme①.如果存在兩個音總是處於自由變異,則它們被視為同一音位的兩個不同音位變體①。
(3)If two phonetically similar sounds② are in complementary distribution, then they are said to be two allophones of the same phoneme.如果語音學上相似的兩個音②處於互補分布, 則稱它們為同一音位的兩個不同音位變體。
(4) If two sounds are in complementary distribution but have no phonetic similarity, then they are certainly two different phonemes.如果兩個音處於互補分布 但沒有語音相似性，則這肯定是兩個不同的音位。
In applying principle (1),we first consider the data given to check whether there is a minimal pair concerning the two sounds under discussion. If yes,then we can arrive at a conclusion that the two sounds are two separate phonemes.
在運用原則(1)時，我們首先考慮所給出的數據，檢查這正在討論的兩個聲音是否存在最小對立體。如果存在，那麼我們可以得出結論，這兩個聲音是兩個獨立的音位。
If no minimal pair can be found, we shall check principle (2), i.e. the case of free variation. But as is mentioned in the footnote of principle(2),it's impossible to find two English sounds to be always in free variation. That is,the answer here is always no.
如果不能找到最小對立體，我們將檢驗原則(2)，即自由變異的情況。但正如在原則(2)腳註中提到的，這是不可能的找到兩個總是處在自由變異的英語發音。也就是說，答案總是否定的。
Now,we shall have to check principle (3),the case of complementary distribution of phonetically similar sounds. If two sounds are not only in complementary distribution, but phonetically similar as well, they are two allophones of the same phoneme.
現在，我們必須檢驗原則(3)，關於語音上相似的兩個音互補分布的情況。如果兩個音不僅處於互補分布，而且語音上也相似，它們是同一音位的兩個音位變體。
Principle (4) is the opposite case of principle (3) in that two sounds are only in complementary distribution but not phonetically similar (i. e. the sounds are phonetically different from each other). Then the conclusion we can reach is that the two sounds are two separate phonemes.
原則(4)是原則(3)的相反情況，即兩個聲音只是處於互補分布，而沒有語音相似性（即，兩個聲音語音上不同於彼此）。我們可以得出的結論是，這兩個聲音是兩個獨立的音位。
Let's come back to the questions raised at the beginning of section 4.4:
讓我們返回到第4.4節開始時提出的問題:
Question (1): Are the two sounds [p] and [b] separate phonemes or different allophones of the same phoneme?
問題 (1): [p]和[b]兩個音是單獨的音位還是同一音位的不同音位變體?
When applying principle (1),we find a minimal pair[Pet] and [bet], and, therefore, come to the conclusion that the sounds [ph] and[b]are two separate phonemes.
在應用原則(1)時，我們找到最小對立體[Pet]和[bet]，因此得出[ph]和[b]是兩個獨立的音位的結論。
Question (2): Are the two sounds [p] and [ph] separate phonemes or different allophones of the same phoneme?
問題(2):[p]和[ph]這兩個音是單獨的音位還是同一音位的不同音位變體?
In checking principle (1), we find that the two sounds [p] and[ph] cannot form minimal pairs.
在驗證原則(1)時，我們發現[p]和[ph]兩個音不能形成最小對立體。
And principle (2) is only a theoretical possibility.
而原則(2)只是一種理論上的可能性。
Then we have to come to principle (3).
然後，我們必須談到原則(3)。
The data given show that the two sounds [p] and [p] are in complementary distribution because they never appear in the same environment:
the aspirated sound [ph] always occurs initially in a word or initially in a stressed syllable, but the unaspirated sound [p] never appears in such environments.
給出的數據表明，[p]和[p]這兩個聲音是處於互補分布的，因為它們從不出現在相同環境中。
送氣音[ph]總是出現在一個單詞開頭或一個重讀音節開頭，而非送氣音[p]從不出現在這樣的環境中。
As to whether they are phonetically similar, we can check the four dimensions used to describe the English consonants (i. e. the position of the soft palate, the presence or the absence of vocalcord vibration, the place of articulation and the manner of articulation) and find that they are, because both of them are oral voiceless bilabial plosives.
至於它們在語音上是否相似，我們可以檢查用於描述英語輔音的四個方面（即，軟顎位置，聲帶的振動與否，發音部位，發音方式），我們發現它們語音上是相似的，因為它們都是口腔清輔音的雙唇爆破音。
Therefore, we can reach the conclusion that the two sounds are allophones of the same phoneme.
因此，我們可以得出結論：這兩個音是同一音位的音位變體。
Question (3): Are the two sounds [h] and [] separate phonemes or different allophones of the same phoneme?
問題(3):[h]和[]兩個音是單獨的音位還是同一音位的不同音位變體?
The case of question (3) is quite similar to that of question (2) in applying the principles
問題(3)與問題(2)在原則的應用上十分相似
(no minimal pair can be found, and the two sounds concerned are in complementary distribution)
(沒有最小對立體，兩個音是處於互補分布的)
except that the two sounds are not phonetically similar
除了這兩個音在發音上不相似之外
(the sound [h] is an oral voiceless glottal fricative while the sound [] is a voiced velar nasal).
(聲音[h]是一個口腔清輔音聲門的摩擦音而聲音[]是一個濁輔軟顎鼻輔音)。
So the final conclusion is that the two soumds [h] and[] are two different phonemes.
所以最後的結論是，兩個soumds [h]和[]是兩個不同的音位。
① Special attention should be paid to the word「always"in principle(2).
應特別注意這個詞「always總是」原則(2)。
As a matter of fact,no two sounds can be found to be always in free variation,at least in English.
事實上，至少在英語中，沒有兩個音可以總是自由變化的。
Therefore,principle(2)is only a theoretical possibility
因此，原則(2)只是一種理論上的可能性。
② To decide whether two sounds are phonetically similar，we can resort to the four dimensions of describing English consonants and the six factors of classifying English vowels,which are discussed in Chapter 3 (Phonetics).
要判斷兩個音在發音上是否相似，我們可以藉助於英語輔音的四個描述方面 和 英語元音的六個分類因素，已在第三章(語音學)中討論過。