I have an Italian language partner who speaks excellent English with almost no [Italian] accent, who asked me if there were any pronunciation corrections I could suggest to her.
One of the very few that I could find was the way in which she transferred to English the Italian 's', usually pronounced as 'z' when a single s, even when it is the first letter of a word.
So I have put my poetic skill to work.
It has come to my attention
to my discerning ear
that there are italiani
who know not what they fear
who seem not to distinguish
the hiss of serpent snake
from the buzzing bumble bees,
when in English these sounds take
a distinct pronunciation
which depends upon the word
in which the hiss or buzzes
take their place so they be heard
When found at the beginning
of any English word
an 's' is always hissing
while not so if it comes third
And likewise when it's second
as in 'is', 'as', 'use' and 'does'
the 's' calls up the bumble bees
and gives the sound its buzz
When it comes in at the ending
to give us more than one,
the 's' denoting plural -
like buzzing, that is done
so hiss at the beginning
and buzz off at the end
and in between you learn the rules
for each new word, my friend.
Your poem isn't completely correct, though. The "s" sound making the plural of nouns can be either "ssss"" or "zzz" depending on the sound before it. If the sound before it vibrates, then the s turns into a z sound.
One cat. Two cats. (sss)
One dog Two dogs. (zzz)