}

    /**
     * Adds a language to filter by.
     * @param lang The language.
     * @return This builder instance.
     */
    public PopularWordsRequestBuilder addLanguage(final String lang) {
        request.addLanguage(lang);
        return this;
    }

    /**
     * Sets the seed for random function.
     * @param seed The seed.
     * @return This builder instance.
     */

     */
    public void addField(final String field) {
        fields.add(field);
    }

    /**
     * Adds a language to filter by.
     * @param lang The language.
     */
    public void addLanguage(final String lang) {
        languages.add(lang);
    }

    /**
     * Sets the detail flag.
     * @param detail The detail flag.
     */
    public void setDetail(final boolean detail) {