Mostly concentrate during the scene when Gwendolen and Cecily having an afternoon tea in the country.
The insults interjected throughout the "Importance of Being Earnest" serve to add humour and unveil the superficial traits of many of the characters.
I believe the following text evidence comes from the section you've cited.
Cecily: This is no time for wearing the shallow mask of manners. When I see a spade I call it a spade.
Gwendolen: I am glad to say that I have never seen a spade. It is obvious that our social spheres have been widely different.
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Gwendolen: I had no idea there were any flowers in the country.
Cecily: Oh, flowers are as common here, Miss Fairfax, as people are in London.
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Gwendolen: Personally I cannot understand how anybody manages to exist in the country, if anybody who is anybody does. The country always bores me to death.
Cecily: Ah! This is what the newspapers call agricultural depression, is it not? I believe the aristocracy are suffering very much from it just at present.
The Importance of Being Earnest
