Online Reference Tools
Dictionaries
Oxford English Dictionary (https://www.oed.com)
Cambridge Dictionary (https://dictionary.cambridge.org)
Merriam Webster Dictionary (Merriam-Webster.com)
American Heritage Dictionary of the English Language (https://www.ahdictionary.com/)
Wordnik (https://www.wordnik.com/)
Collins (https://www.collinsdictionary.com/)
Chambers (https://chambers.co.uk/)
Macmillan (https://www.macmillandictionary.com/)
OneLook (https://www.onelook.com/) +
CD-ROM Dictionaries
Videos:
Using Oxford Dictionary
Using: Cambridge Dictionary
Thesauruses
Thesauruses are more suited to the intermediate and advanced levels.
https://www.thesaurus.com/
https://www.lexico.com/en
Also
Microsoft Word’s Theseauruses Function
Video:
Concordance
Monoconc (www.monoconc.com)
Concordance( www.concordancesoftware.co.uk
Paraconc [ for parallelc orpuses]( www.athel.com)
Wordsmith Tools (http://www.lexically.net/wordsmith/index.html),
Free Concordance
https://www.lextutor.ca/conc/eng/
Video:
Corpuses
British National Corpus (http://www.natcorp.ox.ac.uk/
COBUILD http://www.collins.co.uk
American National Corpus (http://americannationalcorpus.org/)
https://www.english-corpora.org/coca/
Encylopedias
InfoPlease
https://www.infoplease.com/
Bartleby
Scholarpedia
http://www.scholarpedia.org/article/Main_Page
Questia
Encylopedia.com
https://www.encyclopedia.com/
Britannica
Wikipedia
Translators
Linguee
https://www.linguee.com/
Microsoft Translator
WayGo (from Chinese, Japanese, and Korean into English)
Yandex
https://ceviri.yandex.com.tr/?lang=en-tr
Revorso
http://www.reverso.net/text_translation.aspx?lang=EN
Google Translate
Voice Translator & Dictionary (Sesli çevirmen)
SayHi
Word
Tureng
Bing
Zargan