顾客人数可以用英语表示为 "number of customers"。这个短语的来源是通过将两个单词 "number" 和 "customer" 结合起来而形成的。
一些英文例句及其中文翻译如下：
The number of customers in the store increased significantly during the sale. (在促销期间，商店里的顾客人数显著增加了。)
We have to pmit the number of customers in the store at any given time due to COVID-19 regulations. (由于 COVID-19 的规定，我们必须限制商店里任何时候的顾客人数。)
The number of customers visiting our website has been steadily increasing over the past few months. (过去几个月里，访问我们网站的顾客人数一直在稳步增加。)