一个人外出旅游，人生地不熟(be a complete stranger in a place)，最怕的就是被人“敲竹杠”。

“敲竹杠”是一个汉语俗语，字面意思是“beat the bamboo stick”，用来比喻利用他人的弱点或错误敲诈勒索(fleece，take advantage of somebody's being in a weak position to overcharge him)。也可以指借机抬高价格，漫天要价(blatant overcharging)。

例句：

他们大敲游客的竹杠。

They really soaked the tourists.

这简直是敲竹杠。

This is absolutely daylight robbery.

这笔生意听起来好像有点像敲竹杠，我不想做这笔买卖。

This sale sounds like sharp practice to me and I want nothing to do with it.