Using others’ words: When is it plagiarism? When is it fair use?

The examples below draw upon the following passage from the 1985 book, Amusing Ourselves to Death: Public Discourse in the Age of Show Business, by media critic Neil Postman.
Television has achieved the power to define the form in which new must come, and it has also defined how we shall respond to it. In presenting news to us packaged vaudeville, television induces other media to do teh same, so that the total inofrmation environment begins to mirror television.
Respond to the following two prompts/questions:
1. When people plagiarize, they present someone else’s words or ideas as if they were their own. Which of the examples below would be considered plagiarism? Which would not be considered plagiarism? Explain. If you’re not sure, that’s fine. Just explain why you’re uncertain. (Note that we are not concerning ourselves with APA or MLA in this discussion. Pretend you are encountering the examples in a newspaper or magazine, where academic citation style isn’t even used.) 
2. This set of examples has been used by many different instructors. Teachers (both K-12 and higher ed) participate in a culture of sharing that is intended to benefit students and normally isn’t considered plagiarism. Politicians, too, often present words that they did not themselves author. Everyone is aware of the role of political speech writers, and thus this practice is not considered plagiarism. Can you think of other situations where one person presents the words of another without citation, and the practice is not considered plagiarism? What is the difference between the situation you have in mind, or the situations described above, and that of plagiarism that appears in the work of an individual author (whether a student or professional author)?
If you can’t think of a response to #2, or it seems to you that your example has already been well-covered by your peers, then you can respond to the following prompt instead:  Do a little web surfing to learn about a public official or some other prominent person who confronted charges of plagiarism. Summarize the incident and describe any debate surrounding it. 
**This week, please write a subject line for your discussion contribution following the guidelines in this reading on “microstyle.”
Reply to at least one classmate.
Explain or explore any differences between his/her response to #1 and your own. You may also–or instead–want to comment on a classmate’s response to #2.
Original passage as it appears in Postman’s book: “television has achieved the power to define the form in which news must come, and it has also defined how we shall respond to it. In presenting news to us packaged as vaudeville, television induces other media to do the same, so that the total information environment begins to mirror television.” 
Example 1: Television has achieved the power to define the form in which news must come, and it has also defined how we shall respond to it. In presenting news to us packaged as vaudeville, television induces other media to do the same, so that the total information environment begins to mirror television.
Example 2: According to media critic Neil Postman, television has achieved the power to define the form in which news must come, and it has also defined how we shall respond to it. In presenting news to us packaged as vaudeville, television induces other media to do the same, so that the total information environment begins to mirror television.
Example 3: According to media critic Neil Postman, “television has achieved the power to define the form in which news must come, and it has also defined how we shall respond to it. In presenting news to us packaged as vaudeville, television induces other media to do the same, so that the total information environment begins to mirror television.”