You can manage translation by clicking Edit button near a language you want to edit.
Add new translations
To add new translation first you need to chose a section to which translation should apply. Global section is always available in templates, other sections are dedicated to special pages eg: langedit section of admin targeted language corresponds to Language settings page. You can also create a new custom section by clicking Custom section button.
To add new translation lines, click on the edit button and a new empty line should appear.
Enter a keyword name in the first input field - this keyword will be used to access your translation line.
In the second field, enter your translated text.
When done, click on the Save Changes button.
To edit a translation simply click on the Edit button, translation field should now be editable. When done, click Save Changes.
If you want to delete a translation line, click on the Delete button. Translation line will be marked to deletion, and its appearance will change to light red (default). If you change your mind, you can cancel this by clicking Cancel button. When done, click Save Changes
Language management overview: