英语高中语法题，请帮忙快点解答，谢谢~

Question

I thought it strange that he ________ the last examination. ( )
为什么答案是not pass ? 而不是had not passed?

Answer 1

这个是虚拟语气，I thought it strange that he __(should) not pass______ the last examination.
should省略了
句型： It’s necessary (natural, important, strange, a pity, no wonder ,suggested, requested，ordered，demanded, desired..) ＋that 之后以及名词order，suggestion, proposal, request, order等后的表语从句和同位语从句中，其谓语形式为：should+动词原形，should可省。
It’s necessary that he (should) go there himself．
It is a pity that he (should) be absent today.
My suggestion is that we (should) send someone to help him.
I make a proposal that we（should）hold a meeting next week.

Answer 2

should not pass ... (AUX... should) 省略

Answer 3

只说明 没通过考试 是发生在过去的事实 而不与thought构成过去的过去的关系
had not passed表示过去的过去 必须发生在thought之前

Answer 4

这个是虚拟语气。结构：it is strange that + 虚拟语气

Answer 5

it is strange that从句加should do 其中should可省
意思表示表示惊奇不相信
刚刚看外文片 正好也听到了这样的句型哈