Thesis statement can be compared to the key phrase of the paper to be substantiated or discussed. Logically, thesis should be written after formulating essay topic and deciding on the structure. The thesis statement should inform the reader about the author's position in the discussion or the results of their research. Thus, the thesis statement should imply the conclusion the writer has already drawn after processing the information, needed for the essay.
Thesis is normally stated at the end of the introductory paragraph and is composed of one long sentence that covers all arguments the author uses in the discussion. In certain cases, thesis can be expanded, especially when speaking about papers, aimed receiving an academic degree (diplomas or dissertations).
The thesis of shorter essays has the following structure: the first part should include the essay topic and the second part should reflect the author's position. It is also acceptable to introduce an extra part at the end of the essay and briefly explain the reasons for this position. For instance, it would be more reasonable to state "Italy has rich and varied culture due because the Antiquity, the Renaissance and the Modernism influenced it at the corresponding times" instead of "Italy has rich and varied culture".
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