合法的，没得病的，不打疫苗不让进，
非法的，得了病的，敞开边境随便进。
The Biden administration is developing a plan to require nearly all foreign
visitors to the United States to be fully vaccinated against COVID-19 as
part of eventually lifting travel restrictions that bar much of the world
from entering the United States, a White House official told Reuters on
Wednesday. https://www.reuters.com/article/idUSKBN2F52EV
