University of Toronto (Canada)
University of Toronto: Using Computers to Improve Your Writing
Tips from the University of Toronto on using word processing features as aids in composing and revising papers. W.9-10.6 Technology, CCSS.ELA-Literacy.CCRA.W.6, W.11-12.6 Technology
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Clear Ink/spell Web: Let the Web Decide!
A different type of spell checker, giving results from search engines, not based on dictionary word lists, but on frequency of use on the Web. If you're looking for a word that hasn't become official or want to see whether one...