it is clear that without immediate action,she would die from loss of blond and shock

it is clear that without immediate action,she would die from loss of blond and shock
这个句子前半句话it作为形式主语,而is作为谓语,that引导的是整句的主语,那么请问clear在这里作什么成分呢?
这句话中间为何用逗号隔开,如果不用逗号何来呢,那又应该怎么写?麻烦耐心解释下