Is comprehension the same whether a person reads a text onscreen or on paper? And are listening to and viewing content as effective as reading the written word when covering the same material? The answers to both questions are often “no.” The reasons relate to a variety of factors, including reduced concentration, an entertainment mindset (心态) and a tendency to multitask while consuming digital content.

这是 2024 年高考英语新全国卷1阅读C中的一段。

请分析一下And are listening to and viewing content as effective as reading the written word when covering the same material? 这个句子？句子是不是省略了主语啊？另外，麻烦老师翻译一下这个小段。谢谢您！