This site compiles entries from several thesauri to provide synonyms and antonyms for any word a user enters. Each word the thesaurus suggests is itself hyperlinked to other related words, and writers can take the important step of looking up their selected words in the dictionary portion of the site before choosing which best reflects their intended meaning.
Oxford Advanced Learner’s Dictionary Online
An invaluable resource for learners of English, this dictionary provides information on which words take articles and on what prepositions to use, and it provides several sample phrases and sentences to help writers check usage.
Longman Dictionary of Contemporary English
A dictionary designed specifically for English language learners. Not only are words explained in simpler language, but Longman also includes usage examples, common grammar patterns, and collocations (words that are commonly used together with the word being looked up).
Cambridge Learner’s Dictionary Online
(Type the word or phrase you want to look up into the box "Look It Up" box.) A resource that helps with usage more than with definitions, this dictionary provides users with context for their word choices. To see how this dictionary works best, look up the word “fire,” for example.
Merriam-Webster Learner's Dictionary
Another resource for English language learners with definitions and usage examples. Type the word into the Search box.
Phrasal Verbs List
Common phrasal verbs (verb + adverb or verb + preposition), with meanings and examples. Provided by EnglishClub.com.
Learn more about Articles: Choosing a/an, the, or nothing (Ø) with common nouns
In this self-study module, you learn more about solving the mysteries of using a, an, and the by reading explanations, examining examples, and completing some exercises.