When I try to start my program, the npm throws the following error (look below), none of the npm commands can solve the problem. Even if I type $ npm -v only this message shows up. I have macOs mojave, and Node 10.15.3
Error: Cannot find module 'semver'
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:582:15)
    at Function.Module._load (internal/modules/cjs/loader.js:508:25)
    at Module.require (internal/modules/cjs/loader.js:637:17)
    at require (internal/modules/cjs/helpers.js:22:18)
    at Object.<anonymous> (/usr/local/lib/node_modules/npm/lib/utils/unsupported.js:2:14)
    at Module._compile (internal/modules/cjs/loader.js:701:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:712:10)
    at Module.load (internal/modules/cjs/loader.js:600:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:539:12)
    at Function.Module._load (internal/modules/cjs/loader.js:531:3)
MacBook-Pro:zerosBuild Francis$
