book, desk, sun, boy这些还是叫普通名词好。
所谓集合名词就是由两个或两个以上的个体构成的集体名词 比如:wife与husband可以构成一个family(当然还可以加上father, mother, son, daughter等等,反正家庭可由多个个体构成) 当family的意思是family member的时候,就是个体,用的是复数。
比如: The family are watching TV.这就是家庭成员在看电视。
(个体) His family is a big one.(整体) The class are listening to the teacher.(学生们)(个体) The class has made noticeable improvement. 这个班已有引人注目的进步。
(整体) 而police, people, cattle(牛群),就是几个都用复数的集合名词,可译成“……们” The police are searching for the lost boy. 内容来自网友回答
集合的含义