If the south had won the war,___is now the U.S might divided into several countries 为什么填what

题目

If the south had won the war,___is now the U.S might divided into several countries 为什么填what

答案

what是主语从句引导词,what is now the us 是主句的主语
如果南方赢得了战争,现在的美国就可能被分裂为数个国家.