英语句子请帮忙分析结构Thisalonedemonstratesthatthetelevisionbusinessisnotaneasyworldtosurvivein,afactunderlinedbystatisticsthatshowthatoutofeightyEuropeantelevisionnetworks,nolessthan50%tookalossin1989.

Question

英语句子请帮忙分析结构
This alone demonstrates that the television business is not an easy
world to survive in,a fact underlined by statistics that show that out
of eighty European television networks,no less than 50% took a loss in
1989.
这里 a fact 是什么成分?为什么在逗号之后直接加?
同位语？是谁的同位语

Answer 1

this alone demonstrates（ that the television business is not an easy
world to survive in） （that引导的宾语从句）,a fact（同位语） underlined by statistics（过去分词短语作定语,修饰fact） that show that out
of eighty European television networks,no less than 50% took a loss in
1989.( 第一个that 引导的定语从句到全句结束,修饰statistics ,这个定语从句中又包含了个that 引导的宾语从句that out of eighty European television networks,no less than 50% took a loss in
1989.,作show 的宾语.）
a fact 指的就是 that the television business is not an easy world to survive in 引导宾语从句的内容.