Vocabulary in Context is a very efficient way to increase vocabulary whether you learn a foreign language or improve your native language. When you encounter a new vocabulary, it is more effective when you associate the word with its context. That will leave a vivid mark on your memory and last much longer.
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You can use either Chrome or Firefox extension.Install Chrome Extension Install Firefox Add-on
Once you installed browser extension, you read any web pages like you normally do. When you encounter a vocabulary you wish to save, double click that word while holding down Ctrl (Command for Mac) key. The vocabulary and its context (surrounding text) will be saved in the cloud.
Vocabularies appear for your review in Memorize tab based on spaced time interval. You tick (check) vocabulary after you reviewed, and that vocabulary will not show until the next scheduled time.
Use mobile app to review and memorize vocabularies whenever convenient. You can take advantage of short idle breaks. It is more efficient to use several short periods than one long one when learning vocabulary. Allow some of your SNS time on reviewing vocabularies while on the go.