# 1.2 音素（Phonemes）

在自然语音中，不可继续分割的组成部分被称为**音素**（phonemes）。英语的音素分为**元音**和**辅音**。

In natural speech, indivisible sound segments are referred to as *phonemes*. English language categorizes these phonemes into two types: *vowels* and *consonants*.

## 1.2.1 元音（Vowels）

英语总计约有 20 个**元音**。

English approximately has 20 *vowels*.

元音可以被分为短元音（*short vowels*）和**长元音**（*long vowels*）；与此同时，它们也可以分为**单元音**（*monophthongs*）和**双元音**（*diphthongs*）。

Vowels can be classified into *long* and *short* vowels, or alternatively, they can also be grouped as *monophthongs* and *diphthongs*.

| Monophthongs |                              | Diphthongs                              |
| ------------ | ---------------------------- | --------------------------------------- |
| Short vowels | `ʌ` `e` `ə` `ɪ` `ʊ` `ɒ`      |                                         |
| Long vowels  | `ɑː` `æ` `əː` `iː` `uː` `ɔː` | `aɪ` `eɪ` `ɔɪ` `aʊ` `oʊ` `eə` `ɪə` `ʊə` |

严格意义上来讲，`æ` 是半长元音，即，它比长元音短一点，但比短元音长一点。

To put it strictly, `æ` is a mid-length vowel. That means it's a bit shorter than long vowels but longer than short vowels.

## 1.2.2 辅音（Consonants）

英文总计 28 个辅音。

English approximately has 28 *consonants*.

| Airflow   | Voiced or not | Consonants          |
| --------- | ------------- | ------------------- |
| Plosive   | Voiceless     | `p` `t` `k`         |
|           | Voiced        | `b` `d` `g`         |
| Fricative | Voiceless     | `f` `s` `θ` `ʃ` `h` |
|           | Voiced        | `v` `z` `ð` `ʒ` `r` |
| Affricate | Voiceless     | `tʃ` `tr` `ts`      |
|           | Voiced        | `dʒ` `dr` `dz`      |
| Nasal     | Voiced        | `m` `n` `ŋ`         |
| Lateral   | Voiced        | `l`                 |
| Semivowel |               | `j` `w`             |