should have helped是否要改为should help？

问题描述

The above should have helped to clarify these three verbs; you ought now to know how to use them; I must stop writing immediately!

请问：should have helped是否要改为should help？

老师答疑

陈老师：

The above should have helped to clarify these three verbs; you ought now to know how to use them; I must stop writing immediately!

请问：should have helped是否要改为should help？

【1】主语+should have done sth 表示说话者主观上应该做某事却没有做

【2】主语+should do sth 表示说话者给主语提出做某事建议.

以上表达意思不同不可以随便替换.