大家来分析一下这句话中介词短语作什么成分It is difficult to the point of impossibility for the average reader under the age of forty to image a time when high-quality arts criticism could be found in most big-city newspapers.其中it是作形式主语而后面的to do作实际主语,我不清楚的是for这个介词短语作什么成分,是定语还是宾补,还有它前面那个to介词短语.
问题描述：
大家来分析一下这句话中介词短语作什么成分
It is difficult to the point of impossibility for the average reader under the age of forty to image a time when high-quality arts criticism could be found in most big-city newspapers.
其中it是作形式主语而后面的to do作实际主语,我不清楚的是for这个介词短语作什么成分,是定语还是宾补,还有它前面那个to介词短语.
答
此句的构架是：It is difficult to image a time .
for这个介词短语作状语； 它前面那个to介词短语也是作状语.