Question

这个句子with开头是什么结构，看不懂，请帮忙分析一下主谓宾，定状补

It was banks that were on the wrong planet,with accounts that vastly overvalued assets.

Answer 1

句子是强调句没错，去掉it was that:Banks were on the wrong planet,with accounts that vastly overvalued assets. 句子是完整的。
with是介词，后跟accounts这个名词作介词宾语，that引导定语从句，修饰先行词accounts,that在从句中充当主语。整个这个with结构作句子的状语。

Answer 2

这是一个强调句。强调的banks他是主语。were是宾语with引导伴随状语

Answer 3

It was...that... 强调结构句
被强调对象“银行”里的帐户被极大的高估了价值。