By changing the type of obstacle the characters face
The Petrarchan sonnet, perfected by the Italian poet Petrarch, divides the 14 lines into two sections: an eight-line stanza (octave) rhyming ABBAABBA, and a six-line stanza (sestet) rhyming CDCDCD or CDECDE.
Seclude means to keep a somebody away from other human beings.
While, segregate means to separate. For example, in US History, African Americans were segregated from white Americans.
So seclude is used for one person, while segregate is used for groups of people or things.
