What use does Wilde make of the contrast between the city and the country life and values in The Importance of Being Earnest?This question needs an...

The contrast in a work of literature between the simple,
pure innocence of country life versus the sophisticated, worldly excitement of city
life, certainly wasn't a theme invented by Oscar Wilde.  As far back as Shakespeare's
As You Like It (and probably farther), British authors have been
making use of the contrast between the pastoral simplicity of the country life and those
who live there and the worldliness of those who live the more fast-paced (corrupt?) city
life.  So, Wilde knew what his audience would expect of characters found in these two
locales.  And to some degree, he meets their
expectations.

Cecily, for example, is being raised to
become a proper lady in the country.  It is here, it is hoped, that she will cultivate
the fine character of the traditional British lady, without the exposure to the harder
edges city life would bring.  Cecily, however, turns out to be more than just a fading
and innocent country flower.  She stands up to her city counterpart, Gwendolyn, when she
must fight for what she believes is her man against this supposed rival.  There is a
good essay topic here, in examining the ways in which Wilde plays into audience
expectations about characters who live in the country versus those in the city and the
moments in which he reverses these.

Jack, who straddles
these two worlds ("my name is Earnest in town and Jack in the country"), is the
character who has the most to resolve about his identity in the play.  He doesn't know
(until play's end) who his parents were or where he comes from, and he does much
pretending about that --  hence, the personas Earnest and Jack.  So, you could also
create an essay that examines how Jack himself embodies this contrast between the two
locales through creating the "brothers" Jack and Earnest.

I
hope these suggestions help you get started.  Good luck.