The introductory paragraph should act as attention-grabber, as it actually determines the tone and the nature of the discussion. It is a good idea to start the paper with an aphorism, written by a famous person, when writing a literary essay or a paper, explaining a particular social problem. On the other hand, one might prefer to start the essay with relevant statistical data or a theoretical assumption.
It is necessary to keep in mind that the major purposes of the intro are stating the topic and explaining its importance or relevance. Statement of the topic should come in the expanded form, so that the author specifies their approach to the issue and those aspects or components which will be further discussed. Explanation of its importance might not be mandatory, but, logically, it is useful to understand the objective (apart from the subjective like personal preferences) reasons for selecting the present topic. Finally, as it has been mentioned, thesis statement is the last sentence of the introduction.
The length of the introductory paragraph is determined by the volume of the essay and the instructor's requirements. In shorter papers, it constitutes 20 per cent of the total volume, but the intro should not exceed half of the page.
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