It's high time + that 从句谓语动词有两种形式：
动词的过去式(be用were)；或者用shoud + 动词原形（should不能省略)；
句型是虚拟语气句型，意思“现在某人虚岩山该做某事了”。
例句：
1、Therefore, it is high time that parents and schools should be alert to the problem and restrict children's access to those computer games.
因此，现在正是家差中长和学校应该对这个问题提高警觉，限制学生接触电脑游戏。
2、It is high time that we threw away the phone and raised our heads up. Do cherish the ones around us and appreciate the splendid scenery ahead of us.
是时候，我们把电话扔了，抬起头来。珍惜身边的人，欣赏我们在我们前面的辉煌。
3、It is high time that we should tell him the truth.
是咱们该告诉他实情的时刻了。
相关句型：
It's about time that，从句谓语动词同样用过去式或shoud + 动词枣漏原形（should不能省略)。
例句：
1、It's about time that it did. I don't know what took It'so long a time.
差不多是时候了。不知为什么拖了这么长时间。
2、It's about time this old sewing machine was put out to pasture.
这部旧缝纫机大概到了被淘汰的时候了。
