How to write wide and strict phonetic symbols in linguistics?

"Yan Phonetic Alphabet" is used to record "phonemes", and the phonetic symbol is written between square brackets []. "Wide Phonetic Alphabet" is used to record "phonemes", and the phonetic alphabet is written between two slashes//.

The so-called "strictness" means that even slight differences in pronunciation should be recorded with different symbols. Linguistically, these different pronunciations are called "phonemes".

The so-called "width" means that as long as the pronunciation difference does not distinguish meaning, it is recorded with a symbol. Linguistically, the set of phonemes that do not distinguish meaning is called "phoneme". In fact, the sounds that human beings may make are infinite, and it is unrealistic to record all subtle differences.

If phonetic notation is used for a single language, it is enough to ensure that it will not affect the meaning discrimination, so the concept of "phoneme" appears, and "wide phonetic transcription" is the most relaxed phonetic transcription method that can be allowed in practice.

When it is necessary to describe the pronunciation differences of phonemes in different places, or to compare two different languages, "Wide Phonetic Alphabet" is not enough, and different degrees of strictness are needed. Generally, the "strict phonetic alphabet" is only "strict" enough to explain the difference, because it is impossible to accurately record all the minor language changes. ?

Extended materials:

Examples of strict phonetic symbols

1. Comparison of P sounds in pit/spit:

1. P in pit is aspirated sound, marked as superscript in narrow phonetic symbols, and written as [p' hit] (where' is aspirated symbol) < p Writing: [spit]

2. Comparison of L sounds in Leaf/Feel/Build/health:

1. In leaf, L comes before vowels, which is called clear sound, and it is not marked in wide phonetic symbols. Writing: [li:f]

2. In feel, L appears at the end of words, which is called fuzzy sound, and it is narrow. It is also called fuzzy sound, and the inflection symbol [~]

4. In Health, L appears before the dental sound, which is called dental sound [l], and the inflection symbol [II]

Reference: Baidu Encyclopedia-Strict Phonetic Symbol.