Error: Cannot find module 'gulp-clone'问题的解决

安装完gulp环境，并且配置好gulpfile.js，执行静态文件压缩和代码混淆时，出现如下错误：

Error: Cannot find module 'gulp-clone'

Error: Cannot find module 'gulp-html'

配置文件如下：

/**
 * Created by 13
 **/
var gulp = require('gulp');
var clone = require('gulp-clone');
var htmlmin = require('gulp-htmlmin');
var gulpif = require('gulp-if');
var cssmin = require('gulp-minify-css');
var uglify = require('gulp-uglify');
var useref = require('gulp-useref');
var clean = require('gulp-clean');
var imagemin = require('gulp-imagemin');
 
//压缩html
gulp.task('html', function () {
    var options = {
        removeComments: true,  //清除HTML注释
        collapseWhitespace: true,  //压缩HTML
        collapseBooleanAttributes: false,  //省略布尔属性的值 <input checked="true"/> ==> <input checked />
        removeEmptyAttributes: false,  //删除所有空格作属性值 <input id="" /> ==> <input />
        removeScriptTypeAttributes: true,  //删除<script>的type="text/javascript"
        removeStyleLinkTypeAttributes: true,  //删除<style>和<link>的type="text/css"
        minifyJS: true,  //压缩页面JS
        minifyCSS: true  //压缩页面CSS
    };
    return gulp.src('dev-pages/*.html')
    .pipe(htmlmin(options))
    .pipe(gulp.dest('pages/'));
});
//压缩js
gulp.task('jsmin', function() {
    return gulp.src(['dev-source/js/ajax.js','dev-source/js/ajax_my.js'])
        .pipe(uglify({
            mangle: false
        }))
        .pipe(gulp.dest('source/js/'))
})
 
// 拷贝图片文件
gulp.task('image-copy', function () {
    return gulp.src('source-dev/webslice/**/*')
        .pipe(clone())
        .pipe(gulp.dest('source/webslice'));
});
 
gulp.task('image-min', function () {
    return gulp.src('dev-source/images/*.{png,jpg}')
        .pipe(imagemin())
        .pipe(gulp.dest('source/images/'));
});
//先复制图片到source，然后再执行压缩。
gulp.task('image-min2', ['image-copy'], function () {
    return gulp.src('source/webslice/**/*')
        .pipe(imagemin())
        .pipe(gulp.dest('source/webslice/'));
});
 
gulp.task('image-min3', function () {
    return gulp.src('dev-source/webview/img/*.{png,jpg}')
        .pipe(imagemin())
        .pipe(gulp.dest('source/webview/img/'));
});
 
//压缩图片
gulp.task('images-min',['image-min','image-min2','image-min3'],function() {})
 
//监听两个文件的文件变化
gulp.task('listenPages', function() {
    gulp.watch('dev-pages/*.html',['html']);
    gulp.watch('dev-source/js/*.js',['jsmin']);
});
// 构建任务流
// 执行 task build
gulp.task('build', ['html', 'image-min','jsmin']);