Some of our fans ask us to pronounce some idioms from http://www.cantonese.ca/idioms.php
1. 大吉利是 knock on wood (knock the wood). It actually means saying something not quite appropriate at that time so bad luck would come if what is being would come true.
2. 对牛弹琴 play the music to the cow, who cannot understand. Talk to the wrong person.
3. 送羊入虎口 send the sheep to the tiger mouth (feed the tiger with your sheep... to sacrifice, waste)
4. 讲就天下无敌， 做就无能为力 talk like a hero, act like a coward or useless person. Only lip service.
Just go to MDBG.net for the detailed pronunciation and word by word definitions