In the “Translation & Language” tab in your Channel, you will see a list of languages and what type of translation is available for each one (Human, Machine text and Machine speech). Some languages are only listed as 'Human'. These languages cannot be machine translated and can only be human translated.
As shown in the image below the columns a, b and c show which type of translation is available of each language.
If you tick the checkbox under the “Enable Language” column, it means the Reporter may be allowed to choose the language option in the Reporter interface. The interface will also be shown in the chosen language. The Reporter can leave their message in the chosen language.
In the example below you can see Dutch - Vlaams (Belgium) has been enabled for the Channel and it's a Human only translatable language. 
- If you choose to enable a language that can only be translated by a human translator this will incur additional costs for you.