in the first list of words the sound it's like the ü in german in a lot of languages (spanish , italian ) they have not this sound ... in the 2nd list the sounds it's like the u in german , italian , spanish in all the words the sounds ü or u is not differenciate with the voyel after so the sounds ü/u are count as a semi-voyel in all this words ... I hope it can help you so they have special symbol in IPA to make the phonetic sound differents with the simply voyel who is the same sound ....