这是什么从句?that做什么成分?
问题描述：
这是什么从句?that做什么成分?
It has been estimated that if the bridge were packed with cars,it would still only be carrying a third of its total capacity.
答
that 引导的是主语从句,因为太长所以放在了后面,然后用it充当形式主语.正常语序应该是：
that if the bridge were packed with cars,it would still only be carrying a third of its total capacity has been estimated.