Switch the editor window between multilingual or bilingual views depending on your needs:
Multilingual view
This view is very useful for team leaders and contributors working with multiple languages simultaneously. In this view you'll see translations for multiple languages:
To show or hide languages, please use the languages dropdown:
Bilingual view
This view gives maximum space and allows you to focus when working with single language translations:
Choose the source and target languages in the top menu:
The source language (English in the example above) is the language you're translating from. Target (French in the example above) is the language you are translating into.
To hide extra elements and concentrate on translating, you can enable the Focus mode: