1.come undone (鞋带等）松了,线缝等）开了
例句：Lace your boots firmly or the lace will come undone.
把你的靴子系紧，不然鞋带会松开。
2.come up 出现,开始；(为了繁谈等）走上 前来
例句：A beggar came up to us and ask for money.
一个乞丐走过来向我们要钱。
3.come up against 突然地(或意外地）碰到(困难、反对等）
例句：We came up against a great deal of resistance in dealing with the case.
我们在处理该案件时碰到了很多阻力。
4.come up in the world 发迹，兴盛，飞黄腾达
例句：The Whites have come up in the world.
怀特一家已飞黄腾达起来。
5.come up with (针对问题、挑战等）提出, 想出
例句：I came up with them as they were rounding the corner.
他们正在拐弯时，我赶上了他们。
6.come upon 碰上，偶然遇到
例句：I tell you the truth, all this will come upon this generation.
我实在告诉你们，这一切的罪，都要归到这世代了。