title: gulp error: vfs.watch is not a function
body: <p>I have this gulpfile in my office and its working perfectly.
  but when i try to use it at home i get this error and i don't know what is wrong with it. 
  I tried to install all the packages in the dependency and resolve all the error but I cant fix this one:</p>
  
  <p><a href="https://i.stack.imgur.com/FZsut.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/FZsut.jpg" alt="enter image description here"></a></p>
  
  <p>and here is my gulpfile.js</p>
  
  <pre><code>var gulp = require('gulp');
  var sass = require('gulp-sass');
  var browserSync = require('browser-sync').create();
  
  gulp.task('browser-sync', function() {
      browserSync.init({
          server: {
              baseDir: "./"
          }
      });
  });
  
  gulp.task('serve', ['sass'], function() {
  
      browserSync.init({
          server: "./"
      });
  
      gulp.watch("css/*.scss", ['sass']);
      gulp.watch('css/partials/*.scss', ['sass']);
      gulp.watch("css/*.css").on('change', browserSync.reload);
      gulp.watch("*.html").on('change', browserSync.reload);
      gulp.watch("js/*.js").on('change', browserSync.reload);
  });
  
  gulp.task('sass', function() {
  
      gulp.src('css/*.scss')
          .pipe(sass())
          .pipe(gulp.dest(function(f) {
              return f.base;
          }));
  
      gulp.src('css/partials/*.scss')
          .pipe(sass())
          .pipe(gulp.dest(function(f) {
              return f.base;
          }));
  
  });
  
  gulp.task('default', function() {
      gulp.watch('css/*.scss', ['sass']);
      gulp.watch('css/partials/*.scss', ['sass']);
  
  });
  
  gulp.task('default', ['serve']);
  </code></pre>