The most popular free online dictionary that I have personally been using for some time is dictionary.com . It's a useful tool but it is rather verbose in that it gives a lot of information for every word that you look up. When I search for cold (as an example) I receive a long page of information (approx 1,200 words) from ten discreet dictionaries, many of which are American, but very few example sentences.
Cambridge University Press, the oldest publisher in the world no less, have published a free-to-use online version of their dictionary for Learners. The online learners dictionary is far more usable than dictionary.com, especially for people with dyslexia and other reading difficulties. This is thanks to its simple interface, easily read definitions and sample sentences. To compare the two, when I perform the same search for cold I receive a list six possible entries - one for each possible meaning of the word:
Each entry is a link to a separate page containing the definitions and sample sentences for that word. So, for example, if I select the noun form of cold it will show me the following information:
It's concise and easy to read. Another advantage is that with this website if you want to look up one of the words in the definition you can do so simply by double-clicking on it.
The Cambridge Publishing website also has some free interactive online activities for users of the learners dictionary. This includes a drag-and-drop activity where one has to recognise some simple verb patterns, a crossword, and some cloze procedures (fill in the gap) for the use of irregular verbs.
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