You cannot avoid plagiarism by avoiding the use of reference sources. In fact, your institutions want you to refer to multiple sources in order to enrich your assignments. Now, what you may do is to note down all the details regarding a source when you refer to it. For example, note down the information related to the author, publisher, publication year and place, title and referred pages when you are consulting a book. You should also record similar information for any online sources that you refer. For example, you may note down its URL, access date, and author and title information. All this information will be required for developing your bibliography.
Since you are working on a UK assignment, you may be required to follow the Harvard style of referencing. Gain information about this referencing style from your academic institution before citing any reference in your work. This might help you avoid plagiarism to a good extent, as you would know how to quote your sources within text and summarize them. Always ensure to give due credit to your referred source and make sure to include its complete reference at the end of your assignment. Use quotation marks to quote your sources and write the quotation as it exists in its original form. If you are paraphrasing it, then use only relevant details to control plagiarism.
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