请教下老师这个装不上可能什么问题？

cnpm -v 是查得到版本的

wanglimindeMacBook-Air:~ wanglimin$ cnpm install -g @vue/cli

Downloading @vue/cli to /usr/local/lib/node_modules/@vue/cli_tmp

Error: EACCES: permission denied, mkdir '/usr/local/lib/node_modules/@vue/cli_tmp'

npminstall version: 3.28.0

npminstall args: /usr/local/bin/node /usr/local/lib/node_modules/cnpm/node_modules/npminstall/bin/install.js --fix-bug-versions --china --userconfig=/Users/wanglimin/.cnpmrc --disturl=https://npm.taobao.org/mirrors/node --registry=https://registry.nlark.com -g @vue/cli

然后这种vue --version 却发现@vue/cli 是已经安装上的，

再接着cnpm install -g @vue/cli-service-global 又有类似的错误，显示不能安装了

wanglimindeMacBook-Air:~ wanglimin$ vue --version

@vue/cli 4.5.13

wanglimindeMacBook-Air:~ wanglimin$ cnpm install -g @vue/cli-service-global

Downloading @vue/cli-service-global to /usr/local/lib/node_modules/@vue/cli-service-global_tmp

Error: EACCES: permission denied, mkdir '/usr/local/lib/node_modules/@vue/cli-service-global_tmp'

npminstall version: 3.28.0

npminstall args: /usr/local/bin/node /usr/local/lib/node_modules/cnpm/node_modules/npminstall/bin/install.js --fix-bug-versions --china --userconfig=/Users/wanglimin/.cnpmrc --disturl=https://npm.taobao.org/mirrors/node --registry=https://registry.nlark.com -g @vue/cli-service-global

wanglimindeMacBook-Air:~ wanglimin$ @vue/cli-service-global --version

-bash: @vue/cli-service-global: No such file or directory

wanglimindeMacBook-Air:~ wanglimin$ @vue/cli-service-global -V

-bash: @vue/cli-service-global: No such file or directory

wanglimindeMacBook-Air:~ wanglimin$ 

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