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1. sermon
A boring-like speech given for an extended period of time by a so-called expert in his field for the sole purpose of teaching the audience a subject or valuable lesson.

Sermons are often delivered to the audience by total hypocrites, so please tread with caution.
Examples include:

1. Church sermons by a priest/pastor/preacher

2. Commencement addresses at graduation ceremonies

3. Parents to their children whenever they do something the parents used to do that they now feel is wrong
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