Hi IRMA,
Here is a brief explanation of how to set the source language and the target language.
I assume that you want to translate from English to Spanish.
1) type "Tbot change"
2) type the number of your source (=input) language.
3) type the number of the target (=output) language.
//make sure you type numbers for Step2 and Step3 above.
If you want to change Tbot's UI languages, type "Tbot set" and then type the number of your language.
For instance, if you want to read the Tbot commands/instructions in Spanish, type 8.
The site below provides some details on how to use Tbot as well.
http://blogs.msdn.com/b/translation/archive/2010/05/06/bot.aspx
Hope that this is helpful. Let me know how it goes.
Takako (Microsoft Translator Team)