NPM run dev 的问题？

请问输入
‘npm run dev’　
提示　
．．．

@ dev /home/vagrant/Code/sample
npm run development

@ development /home/vagrant/Code/sample
cross-env NODE_ENV=development node_modules/webpack/bin/webpack.js --progress --hide-modules --c onfig=node_modules/laravel-mix/setup/webpack.config.js

sh: 1: cross-env: not found

npm ERR! Linux 4.4.0-81-generic
npm ERR! argv "/usr/bin/nodejs" "/usr/bin/npm" "run" "development"
npm ERR! node v6.11.1
npm ERR! npm v3.10.10
npm ERR! file sh
．．．
是什么原因？