Please don't be deaf to what everybody is saying here these days. With two columns, you can compare two texts line by line. Before, you could translate a whole letter and see the whole letter on screen, now it is impossible, you only see three lines. As someone said, the people who changed the interface are not probably familiar with language learning or translation. The constantly refreshing text when you're typing, I guess it's making many people as nervous as me... Not everything is negative, I like it very much that you included Romanization for some languages and text to speech capabilities but, please... I think the two-column issue is almost unanimous. Please everydoby insist so that they listen to us.
