In what way is Pygmalion is a play about speech and phonetics?

is all about speech and

phonetics, which are the cornerstones of the British experience of social
class.

At the start of the play, Henry Higgins gambles
with Pickering over his experiment with
Eliza's speech; by making the bet in
the first place, Higgins is treating the acquisition of
so-called "proper"
speech and pronunciation as a sport, which reflects Higgins's
position of
privilege within British society. Only someone so confident in his or her
position
could make light of it in this way.

Later in the
play, Eliza is very
convincing after she has been schooled by Higgins, which
suggests that social class is utterly
meaningless; if the trappings of high
class can be learned so quickly and so thoroughly by
someone of such low
position as a flower seller, what value does it carry, really?

Ironically, though Shaw might be able to make the meaninglessness of speech
and
phonetics apparent, through Higgin's treating speech like a sport and
through Eliza's rapid
progress, the harsh reality still persists: speech and
phonetics in Britain remain significant
markers of class that divide the
people of Britain still to this day.