How to pronounce 沉底 in Cantonese (4 out of 5):

心口要沉底
My heart is deep.

Cantonese Sentence Breakdown

心口 hung1 hau2
chest
jiu3
important
vital
to want
to ask for
will
going to (as future auxiliary)
may
must
(used in a comparison) must be
probably
if
essential points
necessary
necessity
to desire
to need
should
沉底 zam6 dai2
(verb) sink to the bottom; sunken