a pair of a loaf of a packet of a comb of这些量词啥意思?

英语量词搭配a pair of a bottle of a packet of a bag a cup of a gia a loaf of bread a packet of ( ? ) a packet of piaying 什么词性前必须用 如 a piece of / a loaf of / a pair of / 这些词来修饰. 四年级上册英语音标a packet of sweetsa loaf of breada bowl of noodlesa 不可数名词量词使用A piece of cheeseA loaf of bread A bar of soapA bar A pair of glasses ___(be) fifty yuan.A packet of sweets__(be a pair of shoes a pair of couple a pair of a pair of ( )