后面加上字母o，可以组成单词who，意思是：pron.谁(询问姓名、身份或职务)什么人表示所指的人进一步提供有关某人的信息。
例句：1.Well， what do you know? Look who's here!
唷，真想不到！你看谁来啦！
2.Who would have thought to find you here?
谁会料到你在这儿呢
3.Health care must be at the service of all who need it.
医疗保健机构必须为所有需要者提供服务。
