Coronaviruses are_____viruses that typically affect the_____system of mammals, including humans.
A. a kind of; digestion
B. a family of;respiratory
C. /; SARS
D. many; blood circulation
查看答案
Since the o_______ of Covid-19 last December, thousands of Chinese has been under quarantine.
WHO的全称是world health organization, 即世界卫生组织。
A. 对
B. 错
Please match the words and phrases with their Chinese translation.
执行语句“for(i=1;i<9; i++);”后变量i的值是______。
A. 10
B. 9
C. 8
D. 7
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