Changes in final consonants in Southern Vietnamese

 In Northern Vietnamese, most ending consonants are pronounced the same as at the beginning of the word. One of the few exceptions is "-ch", which usually becomes a "c" sound. However, in Southern Vietnamese, many endings change compared to the spelling. Following is a list of these changes.

1. -t -> -c
This change only applies to words where the syllable nucleus is not either an i or an ê. For example, nhất becomes nhấc, but con nít stays con nít.

2. -n -> -ng
Same as above. Example: bạn -> bạng, but tên stays tên

3. -ch -> -t
Applies to all words. Example: thích -> thít

4. -nh -> -n
Applies to all words. Example: hình -> hìn

One issue with the above is whether or not rules compound. For example, if mạnh changes to mạn according to rule number 4, shouldn't then rule number 2 be applied, so that the final result is mạng? But this is generally not the case according to my experience. But if the -t changes to -c and the preceding vowel is an u, ô or o, then the rule of closing the mouth while simultaneously pronouncing the ending does apply usually. This can be observed in words like tốt or rút.

Video with example clips:

https://youtu.be/9rkPG37Z1tc