There are three types of seasonal influenza – A, B and C. Type A influenza viruses are further typed into subtypes according to different kinds and combinations of virus surface proteins.

有三种类型的季节性流感——甲型、乙型和丙型。 根据病毒表面蛋白不同的种类和结合情况，甲型流感病毒又进一步分类为亚型。

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However, PHP itself is written in c, and memory problems deep in PHP's core surface occasionally.

然而，PHP本身也是使用c语言编写的，有时记忆问题深至PHP的核面。

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Say when you're at the front of C prime, your thumb points to the right, your index points up because that's where the surface is, and then your middle finger will point out.

你在曲线C的前端，你的拇指指向右边，你给指出来了，因为那就是这个表面所在，然后你的中指就会指出。

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