1. The sounds /p,t,k,m,n/ and the sound /n/ as in 'sing' in final position.
The above six sounds exist in Chinese, but when the occur at the end of a syllable they are never 'released',i.e. For /p/ and /m/ the lips remain closed; for /t/ and /n/ the tongue tip clings to the roof of the mouth; and for /k/ and /n/ the back of the tongue clings to the roof of the mouth. Chinese speakers will transfer these articulatory habits to English, and consequently these sounds seem to be 'swallowed' and the English listener may have difficulty hearing which sounds was produced. (This is so even though English speakers themselves occasionally do not release these sounds at the end of words.
2. Chinese does not have either of the 'th' sounds.
Learners will substitute either /t/ or /f/ for /θ/ as in 'thick' and either /d/ or /v/ for /e/ as in 'this'. /f/ and /v/ substitutes cause more problems.
3. Chinese does not have /v/ as in 'van' although /f/ as in 'fan' does occur.
At the end of a word learners tend to substitute /f/ for /v/, so 'save' will sound like 'safe'.
At the beginning of a word learners tend to substitute /w/ for /v/, so 'vine' will sound like 'wine'. Cantonese speakers may show confusion with /b/ or /p/
4. Although /t / as in 'church' does occur in Chinese (the name 'Choy') /d/ does not, so learners will not be able to distinguish or produce a difference between 'Choy' and 'joy' (initial position) or 'rich' and 'ridge' (final position).
5. Although /b, d, g/ occur at the beginning of words in Chinese and Cantonese, they do not occur at the ends of words. Learners will tend to substitute /p, t, k/. However, these are not very adequate substitutes for the reason stated above.
6. Chinese has /s/ but no /z/.
// as is 'she' is a common substitution for /z/. Practice will be needed in both initial and final position.
7.// as in 'she' does not exist as a separate sound in Chinese.
Learners will commonly substitute /s/ for this sound, so pairs like 'see', and 'she', 'same' and 'shame' will be problematic. This situation is complicated by the fact that before the /u/ sound as in 'moon' learners will substitute / for /s/, so they will pronounce 'Sue' as 'shoe'. This is because /  / is a variant of the /s/ sound before this particular vowel. The problem is not making the sound /  /, but what sound comes next.
***/  / does exist in Mandarin Chinese, so if learners are familiar with Mandarin it may help to mention this (but it will probably not help the problem before the vowel /u/).
8. // as in 'rouge' does not exist in Chinese.
9. Confusion between /l/ and /r/.
There is a well-know perceptual confusion between these two sounds, and a production difficulty.
Learners have a tendency to use a sound which sounds most like and /r/ to the English ear for both sounds:
'all' may sound like 'or'
'fell' may sound like 'fear'
'fall' may sound like 'four'
but in initial position an /l/-like sound is often substituted for /r/:
'ride' may sound like 'lied'
'raid' may sound 'laid'
The same problems occur when these two sounds are grouped with other sounds in a sequence or a cluster:
'blue' may sound like 'brew'
'flight' may sound like 'fright'
'clutch' may sound like 'crutch'
10. /n/ and /l/ confusion.
Some Chinese speakers may have difficulties perceiving and producing these sounds before vowels.
11. /t/ and /d/ confusion ('town – down').
This is a problem for Cantonese speakers, who will not use enough aspiration for /t/.
Teacher~Jeffrey