How to pronounce 衰退 in Cantonese (7 out of 9):

其實 唔係因為智能衰退所以人類文明減亡
It's not that the human civilization is declining because of declining intelligence.

Cantonese Sentence Breakdown

其實 kei4 sat6
actually
唔係 m4 hai6
(phrase
adverb
noun) no, not.
因為 jan1 wai6
due to
智能 zi3 nang4
intelligence
smart
衰退 seoi1 teoi3
decline
所以 so2 ji5
hence
人類 jan4 leoi6
humanity
文明 man4 ming4
civilization
gaam2
reduce
mou4
same as無, not a