‘ adults in the United States who have not yet received ……

'adults in the United States who have not yet received a COVID-19 vaccine'

這限製性定語，講了三要素：成人；在美國；以前沒有接種過疫苗。

 

完蛋了，總統（白等）了。俺去年初打了兩P，還指望著用這玩藝當B呢。