Well, here we have to clarify some things. In Spanish, the "LL" combination is pronounced the same way as "Y" when "Y" is at the beginning of the word. For example, in the word "lluvia" (rain) you pronounce "LL" exactly as "Y" in the word "yo" (I). In Catalan, the double L is pronounced the same way as in Spanish, BUT if you see a dot between the "L's", that means that you have to pronounce a longer "L". Here is an example: the word "al·lèrgia" (allergy) is pronounced as "aLergia", not "ayergia".