WordSwap

WordSwap is the easiest way to build vocabulary in a foreign language. There's no reason to go out of your way to view flashcards or listen to audio for 30 minutes a day. Instead, just turn the extension on and read content online as you normally do. You'll pick up the new words in a passive manner as they appear in the text you read.

The extension works by swapping out foreign language words each time it appears on a page. You create a list of words by entering word-pairs in the settings window (just click on the extension's icon at the top-right corner of the browser to change the settings).

Be sure to click "Enable Swapping". You can also choose to see the original word next to the foreign word and/or see the foreign word highlighted in the text.

Please let us know if you have any suggestions or experience any problems.