在英语中，"我来买单"可以翻译为 "I'll take care of the bill." 这个表达来源于一种习惯，即在餐馆或酒吧等场所，由一个人来支付所有人的消费账单。

例句：

"I'll take care of the bill tonight. You can get it next time." (今晚我来买单。下次轮到你了。)

"Don't worry about the bill. I've got it covered." (别担心买单。我来搞定。)

"Can you split the bill with me? I don't have enough cash on me." (你能跟我分一下买单吗？我身上没带够钱。)