How to avoid accidental plagiarism: some strategies

Expect to acknowledge everything you've got from a source other than your own head. The things that don't need referencing are your own ideas and common or uncontroversial knowledge (English is a Germanic Language, for example). If in doubt, err on the side of over-referencing, until you get the knack. Having too many references in a text breaks up the flow of your writing, but that is the lesser of two evils. To avoid too much repetition, you may be able to say at the beginning of a section or paragraph: The following is a summary of information given in Smith (1994). Note, however, that it is not sufficient to give one vague reference to your source somewhere, and then draw directly from it for page after page.

Rather than just summarizing what you are reading for the sake of it, make notes relevant to the task in hand and identify the major points that relate to your purpose. Make the notes under headings; you can then write out your own version based on those points. When making notes, use your own words wherever possible. Never copy anything out without putting it in inverted commas and putting a page reference next to it. Always keep the full reference details for any source you draw on, as you will need them later. These details should be integral to your notes, so that you can easily see where an idea or quote has come from.

Where your source text gives examples of a phenomenon under discussion, try to think of some examples of your own (or look them up in a dictionary or another book). This is in any case a good way of ensuring that you understand what you are writing about. However, if you are in doubt about whether your example is valid (e.g. where the examples have been drawn from a particular source that you cannot access), quote the ones you have been given and acknowledge them appropriately. If there is any terminology you don't understand, look it up, don't just copy it out.

From Projects in linguistics by Alison Wray, Kate Trotter and Aileen Bloomer, Arnold 1998, p. 242