2017年12月四级阅读中句子：Even men and schoolchildren are swelling the ranks, among them my friend's three small grandsons. 其中的among them my friend's three small grandsons属于名词+介词短语独立主格。但正常语序应该是my friend's three small grandsons among them.这里后半部分并不是太长，为什么要用倒装。当改成完整句时my friend's three small grandsons are among them会是一种常见倒装情形among them are my friend's three small grandsons.是否这种完整形态的倒装习惯影响了独立主格形式的表达？这种独立主格中同时有倒装是纯属习惯？还是有语法意义（为了强调？或是简洁？）