So, here is the symbol for C and the staff here is where C would be located on the keyboard.

这是C的符号,这里是C在键盘上的位置

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And most of these commands you don't actually need but this little caret symbol means control, so every keyboard these days has a control key so you hold that and hit X for instance to exit the program.

这里大多数命令你们都用不着,这个小插入符意味着控制，每个键盘都有一个控制键,譬如，当你敲入X时，就退出这个程序。

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