In Lady Windermere's Fan, explain the expository effect of Act I..

There are events that stand out on the first act of
Lady Windermere's Fan.

The first is
when Lady Windermere's butler asks her if she will be available for visits and informs
her that Lord Darlington will be  stopping by the house. Lady Windermere reacted with
hesitation at this information, leaving the audience wondering what could be
happening.

This may seem unimportant but, as Lord
Darlington enters and begins his conversation with Lady Windermere, we learn that the
night before he had been making uncomfortable comments and paying excessive compliments
to her. The way in which Lady Windermere  tells him that he should not do that
again, makes the audience sense that there is a subtle but mutual attraction between
Lady Windermere and Lord Darlington. However, Lady Windermere is quite clear in her
duties to her husband, and in her dignity as a lady.

Act
I also shows when the Duchess of Berwick visits Lady Windermere and discloses the rumor
that is going all over London: That Lord Windermere is financially supporting a woman
known as Mrs. Erlynne.

These two situations are the factors
that set the plot in motion: First, when Lady Windermere confronts her husband about the
rumors is when we realize that Lord Windermere is secretly trying to get Mrs. Erlynne
back in society so that she can disclose that she is Lady Windermere's
mother.

Second, when Lady Windermere loses her nerve out of
the anger that her husband has caused her she runs straight to Lord Darlington for
comfort and, perhaps, for a romantic meeting with Darlington to get back at her husband.
This directly contradicts her previous behavior in which she showed signs of annoyance
at his advances.

Concisely, the expository events of Act I
present the conflict of the story and also foreshadow what could become of the
relationship of Lady Windermere with Lord Darlington.