新概念中的句子分析

是的，虚拟语气，与现在事实相反的假设用过去时；与将来时间相反的时候就用过去将来时。

在虚拟语气的从句中，动词'be'的过去时态一律用"were"，不用was， 即在从句中be用were代替。
If I were you, I would go to look for him.
如果我是你，就会去找他。
If he were here, everything would be all right.
如果他在这儿，一切都会好的。

典型例题
_____ to do the work, I should do it some other day.
A. If were I B. I were C. Were I D. Was I
答案C. 在虚拟条件状语中如果有were, should, had这三个词，通常将if省略，主语提前, 变成 were, should, had +主语的形式。但要注意，在虚拟条件状语从句中，省略连词的倒装形式的句首不能用动词的缩略形式。如我们可说 Were I not to do., 而不能说 Weren't I to do.

是虚拟 如果桥上挤满了车 运用虚拟必须用were 因为不是事实嘛 例如 if I were you ，如果我是你 用were 也不用was

were表示的虚拟假设