1、首先，是对将来情况的虚拟。例子：If he should go home,he would choose this road.
2、然后，是对现在情况的虚拟。例子：If he lived in HeiBei,he would know the enviornment.
3、最后，是对过去情况的虚拟。例子：If he had watched this TV show,he might have told me about this.
1、首先，是对将来情况的虚拟。例子：If he should go home,he would choose this road.
2、然后，是对现在情况的虚拟。例子：If he lived in HeiBei,he would know the enviornment.
3、最后，是对过去情况的虚拟。例子：If he had watched this TV show,he might have told me about this.