These sites are wonderful
How to Improve Conversation Skills
Conversation Skills
You can teach them (1) vowel musicality through minimal pairs and sets
minimal pairs: set - pet / big - pig / pin - bin / ferry - very
minimal sets: feel - fell - fall - fuel - fool - fill - foal - full - file - foul
boot - but - beet - bout - bat - bit - bite - bet - boat
(2) word/sentence stress: present -v present -n
(3) intonation (rising/faling) ..etc
Wish you all the best



