03:30 Jul 9 

@Victor- It's a children's encyclopedia and the chapter has different questions on the same topic. For e.g. " Wie sind Gebirge entstanden"?. Now, in this question can't "Gebirge" be just translated as "mountains" instead of "mountain ranges"??

14:05 Jul 8 

If the word "Berg" in the article is ambiguous (sometimes meaning mountain, sometimes hill), Bhavna's comment that "the distinction has to be very clear" because of the frequent use of the word could be dangerous. If the word means different things in different contexts in the text, this must be taken into account in the translation. Of course this means more work, and in some cases it could mean rewriting the text, but that is what professional translation is about.

13:13 Jul 8 

What does the encyclopedia article cover? The word "Berg" can also be used for small hills. In north-east Germany there are plenty of "Berge" which rise to less than a hundred metres above sea level (i.e. "hills" in English).
I agree with Gebirge = mountain ranges (although it could also mean high mountains). The "rock formation" option is only relevant in geology or mining contexts.

11:43 Jul 8 

My dictionary gives two possible translations: a) mountain range ; b) rock formation.