帮我讲一下虚拟语气方面知识

虚拟语气是英语中用来表示对不可能发生的事物的一种猜测或假设的语气。英语中的虚拟语气常见的类型有:条件状语从句中的虚拟语气，后宾语从句中的虚拟语气，某些动词后宾语从句中的虚拟语气，某些结构后主语从句中的虚拟语气等。本课中出现的条件状语从句中的虚拟语气，本将只讨论条件状语从句中的虚拟语气。

"if"条件状语从句中的虚拟语气的结构如下表：
虚拟类型从句主句
对现在情况的假设一般过去时would+动词原形
对将来情况的假设一般过去时would+动词原形
对过去情况的假设过去完成时would + have + 过去分词

一、对现在情况的假设

本课课文中出现了虚拟语气,主要表示对不可能发生或不太可能发生的现在情况的假设，其中使用虚拟语气的句子有:

1)If you were an Inuit near the North Pole, you would enjoy the raw meat from seals.
2)If you were a man living in the grassland, you would prefer the roasted meat of sheep or goats.
3)If you were in Germany, you would find soup that is thick and heavy.
4)If you were in China, you would find soup that is thin and clear.

以上各句所体现都是条件状语从句中的虚拟语气，表示对不可能发生或不太可能发生的现在情况的假设。
对现在情况假设的虚拟语气的构成如下：

1）条件状语从句中用were,而主句中则用would + enjoy 构成
2）条件状语从句中用were,而主句中则用would + prefer 构成
3）条件状语从句中用were,而主句中则用would + find 构成
4）条件状语从句中用were,而主句中则用would + find 构成 <