pour répondre à toutes tes questions, bah d'abord le premier c'est "a loanword", et la deuxième réponse, le sang is an adjective et la neige is an objective case. good luck to your study:)
so far as i see, the example of "boules de neige" doesn't quite fit. coz its verbal equivalent in the english language is snowball, which is one single word, but not snow ball, a noun phrase. so its not safe to say snow here serves as an adj.
i think " neige" and "sang" are uncountable. Thus, we use "boucle(s) de" ,"un flot de" to qualify "neige" and "sang"???
errr, u meant to say quantify? might be so for "un flot de sang". like we say in english, a flow of sth, indicating a large quantity of sth. as for "boule de neige", i tend to understand it as a whole, just like we say in french, une pomme de terre. and that's that. je cherche pas plus loin. une boule de neige, meaning a snowball. same case for une boule de feu, ou bien une boule de crystal. "une boule de" here shouldn't be taken as a quantifier or sth similiar. saying a ball of sth. two balls of sth, it doesn't make much sense to me.
the regular translation of bus stop in french is l'arret d'autobus. a general term that can be used to refer to any bus stop. the part "d'autobus" functions as an adjective, same role as the noun "bus" in the noun phrase bus stop. but in the given context, only one specific bus stop is involved, whichi is the one where tht target would show up. so the bus stop here should be translated into l'arret de l'autobus just to keep the same idea of "specialness".
提升卡
沉默卡
喧嚣卡
千斤顶
楼主 
。。。。。。。。。
