AuthorAid
http://www.authoraid.info/
Provides many resources about science writing for non-native English speakers in its extensive resource library. Topics include grammar, writing papers for scientific journals, and responding to journal editors and reviewers.  

Scientific English as a Foreign Language
http://users.wpi.edu/~nab/sci_eng/
Gives English language lessons developed by native English-speaking researchers. Most lessons explain English grammar concepts or differences between commonly confused words.  

Purdue Online Writing Lab (OWL) for Students of English as a Second Language
http://owl.english.purdue.edu/owl/resource/678/01/
Explains parts of speech, has grammar exercises, and introduces the concept of workplace writing. The site links to the extensive resources of the OWL program.  

UsingEnglish.com
http://www.usingenglish.com/
Includes an English grammar glossary and lists of English idioms, irregular English verbs, and English phrasal verbs. The site includes quizzes and tests and forums.  

One Look Dictionary Search
http://www.onelook.com/
Searches multiple dictionaries at once, including general, medical, science, and other specialized dictionaries.  

The Idiom Connection
http://www.idiomconnection.com/
Provides lists of idioms and their explanations organized by alphabet and by subject.  

Presentation Tips for Non-native Speakers
http://sciencecareers.sciencemag.org/
career_magazine/previous_issues/articles/2011_06_17/caredit.a1100056
Offers presentation tips for non-native speakers and gives sample slide presentations (from Science Careers [Science]).     

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Updated August 2011