新华社日内瓦6月5日电(记者刘曲)世界卫生组织5日发布使用口罩预防新冠的最新指南,就哪些人群应佩戴口罩、何时佩戴以及口罩应使用何种材料等给出最新建议。
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President Xi: China and France should jointly prevent a new cold...
By Chris Michael
“As the world goes through transformation and turbulence not seen in a century, China and France should uphold their independence and jointly...