请问这个句子对吗?it is not necessary for all to speak standing.

问题描述:

请问这个句子对吗?it is not necessary for all to speak standing.
it is not necessary for all to speak standing.
这里的standing在句中作什么成份?standing是作to speak 还是standing作状语修饰to speak?

做伴随状语修饰speak 这个动作详细一点好吗?这句话中it为形式主语,真正的主语是不定式to speak standing,其中standing做状语修饰speakstanding作为分词应有主语,那它的主语是谁?它的逻辑主语是all