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The tone of a text refers to the feeling that the author of a text wants the reader to feel at the moment he is doing the reading. This tone promotes an atmosphere that intensifies the theme that the author is addressing. In this case, the author can promote a happy tone to reinforce the idea of achievements, progress, happiness, among other happy situations, as well as a sad tone to reinforce pessimism and defeat, a surprised tone to reinforce suspense and so on.