迄今为止，甲型流感病毒血凝素HA共发现有（）个亚型、神经氨酸酶NA有（）个亚型。
参考答案：16；9
Can you share a book with him ？We’ll let you have a new one next Monday.
A．at a time
B．all the time
C．for the time being
D．at one time
将RNA核苷酸顺序的信息转变为氨基酸顺序的过程是
A．复制B．转录C．反转录D．翻译
