It's simpler than you think. It uses Google Translate to translate the word or phrase you select and the context isn't used. This works surprisingly well most of the time. Of course it does fall down, and can be confusing beginners who don't have a good grasp of the basic grammar. For intermediate and advanced users who just need the occasional gap filled it it's great, and they can usually tell when the translation isn't correct and either expand the phrase to add more context, or make use of the additional sidebar dictionary: https://readlang.uservoice.com/knowledgebase/articles/279539...