Confused with "parlez d'"

Question

I don't understand thisFrench: "Vous parlez d'autres langues"English "Are you speaking about other languages?"if "de" comes from "parlez", the lesson says it needs to be contracted to "des"but here, it's just "d'"

Accepted Answer

Aung, 
I remember that this lesson confused me for a while .
However, this example/quiz question is general ‘ (about/of ) other languages ‘. It is not specific ‘ about/of the other languages ‘.  
If you have a look back at section 2, you will see that the examples, using parler de, cover this.
Have a reread of the lesson, especially the ‘ attention ‘ note under section 1 -  importantly it will never be ‘ des autres ‘ for the English equivalent of some/any (words often dropped in English, but the French indefinite/partitive cannot be dropped ).
From section 2
des autres is the contraction here of [de + les autres] (about/of the others), so it implies that we're talking about specific things here (the others), 
whereas using d'autres here is the contraction of [de + autres] (about/of others) is less specific ([some] others).