come up最常用的五种官方意思是什么?

这是英语必修一第二单元的重点词组：
1.开始;发生
I'll let him know if anything comes up.
如有什么事,我会告诉他的.
2.被提出,被讨论
A number of questions came up at the meeting.
会议上提出了许多问题.
3.走过来
She came up and said,"Glad to meet you."
她走过来说,"很高兴见到你."
4.开始流行
5.发芽
6.上升（太阳.月亮等）
常考第2点,不用被动