Question

purpose of for when used as a coordinating conjunction (it's usually a preposition though)

Accepted Answer

introduce a reason for the previous clauseJohn thought he had a good chance to get the job, for his father was on the company's board of trustees.

Front	purpose of for when used as a coordinating conjunction (it's usually a preposition though)
Back	introduce a reason for the previous clause John thought he had a good chance to get the job, for his father was on the company's board of trustees.

Purpose When Coordinating Conjunction Preposition Introduce Reason Previous