中考英语阅读理解训练+答案解析选择最佳选项 Its been over a year since COVID-19 first appeared and the virus continues to be a problem in many parts of the world, scientists have realized the development of vaccines (疫苗) is a solution to the pandemic. A global effort to vaccinate as many people as possible would be needed, since vaccines typically take years to develop. On Dec 2, 2020, the first COVID vaccine, the Pfizer vaccine, was approved (批准) by UK health department. However, these vaccines must b
