I am typing npm install -g firebase-tools but terminal gives me this message: 
我正在输入npm install -g firebase-tools但是终端给了我这个信息：
checkPermissions Missing write access to /usr/local/lib/node_modules npm ERR! checkPermissions缺少对/ usr / local / lib / node_modules npm ERR的写访问权！ path /usr/local/lib/node_modules npm ERR! 路径/ usr / local / lib / node_modules npm错误！ code EACCES npm ERR! 代码EACCES npm ERR！ errno -13 npm ERR! errno -13 npm错误！ syscall access npm ERR! syscall访问npm ERR！ Error: EACCES: permission denied, access '/usr/local/lib/node_modules' npm ERR! 错误：EACCES：权限被拒绝，访问'/ usr / local / lib / node_modules'npm ERR！ { [Error: EACCES: permission denied, access '/usr/local/lib/node_modules'] npm ERR! {[错误：EACCES：权限被拒绝，访问'/ usr / local / lib / node_modules'] npm错误！ stack: npm ERR! 堆栈：npm ERR！ 'Error: EACCES: permission denied, access \\'/usr/local/lib/node_modules\\'', npm ERR! '错误：EACCES：权限被拒绝，访问\\'/ usr / local / lib / node_modules \\''，npm ERR！ errno: -13, npm ERR! errno：-13，npm错误！ code: 'EACCES', npm ERR! 代码：“ EACCES”，npm错误！ syscall: 'access', npm ERR! syscall：“访问”，npm错误！ path: '/usr/local/lib/node_modules' } npm ERR! 路径：'/ usr / local / lib / node_modules'} npm ERR！ npm ERR! npm ERR！ The operation was rejected by your operating system. 该操作被您的操作系统拒绝。 npm ERR! npm ERR！ It is likely you do not have the permissions to access this file as the current user npm ERR! 您可能没有权限以当前用户npm ERR的身份访问此文件！ npm ERR! npm ERR！ If you believe this might be a permissions issue, please double-check the npm ERR! 如果您认为这可能是权限问题，请仔细检查npm ERR！ permissions of the file and its containing directories, or try running npm ERR! 文件及其包含目录的权限，或尝试运行npm ERR！ the command again as root/Administrator (though this is not recommended). 再次以root / Administrator身份执行命令（尽管不建议这样做）。
npm ERR! npm ERR！ A complete log of this run can be found in: npm ERR! 可以在以下位置找到该运行的完整日志：npm ERR！
/Users/skltn/.npm/_logs/2018-07-08T19_03_42_011Z-debug.log Skeletons-MacBook-Pro:~ skltn$ firebase --help -bash: firebase: command not found Skeletons-MacBook-Pro:~ skltn$ firebase -login -bash: firebase: command not found Skeletons-MacBook-Pro:~ skltn$ npm install -g firebase-tools npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules npm ERR! /Users/skltn/.npm/_logs/2018-07-08T19_03_42_011Z-debug.log Skeletons-MacBook-Pro：〜skltn $ firebase --help -bash：firebase：找不到命令Skeletons-MacBook-Pro：〜skltn $ firebase -登录-bash：firebase：找不到命令骨架-MacBook-Pro：〜skltn $ npm install -g firebase-tools npm WARN checkPermissions缺少对/ usr / local / lib / node_modules npm的写入权限！ path /usr/local/lib/node_modules npm ERR! 路径/ usr / local / lib / node_modules npm错误！ code EACCES npm ERR! 代码EACCES npm ERR！ errno -13 npm ERR! errno -13 npm错误！ syscall access npm ERR! syscall访问npm ERR！ Error: EACCES: permission denied, access '/usr/local/lib/node_modules' npm ERR! 错误：EACCES：权限被拒绝，访问'/ usr / local / lib / node_modules'npm ERR！ { [Error: EACCES: permission denied, access '/usr/local/lib/node_modules'] npm ERR! {[错误：EACCES：权限被拒绝，访问'/ usr / local / lib / node_modules'] npm错误！
stack: npm ERR! 堆栈：npm ERR！ 'Error: EACCES: permission denied, access \\'/usr/local/lib/node_modules\\'', npm ERR! '错误：EACCES：权限被拒绝，访问\\'/ usr / local / lib / node_modules \\''，npm ERR！ errno: -13, npm ERR! errno：-13，npm错误！
code: 'EACCES', npm ERR! 代码：“ EACCES”，npm错误！ syscall: 'access', npm ERR! syscall：“访问”，npm错误！ path: '/usr/local/lib/node_modules' } npm ERR! 路径：'/ usr / local / lib / node_modules'} npm ERR！ npm ERR! npm ERR！ The operation was rejected by your operating system. 该操作被您的操作系统拒绝。 npm ERR! npm ERR！ It is likely you do not have the permissions to access this file as the current user npm ERR! 您可能没有权限以当前用户npm ERR的身份访问此文件！ npm ERR! npm ERR！ If you believe this might be a permissions issue, please double-check the npm ERR! 如果您认为这可能是权限问题，请仔细检查npm ERR！ permissions of the file and its containing directories, or try running npm ERR! 文件及其包含目录的权限，或尝试运行npm ERR！ the command again as root/Administrator (though this is not recommended). 再次以root / Administrator身份执行命令（尽管不建议这样做）。
npm ERR! npm ERR！ A complete log of this run can be found in: npm ERR! 可以在以下位置找到该运行的完整日志：npm ERR！
/Users/skltn/.npm/_logs/2018-07-08T19_05_23_066Z-debug.log Skeletons-MacBook-Pro:~ skltn$ /Users/skltn/.npm/_logs/2018-07-08T19_05_23_066Z-debug.log Skeletons-MacBook-Pro：〜skltn $
