封面文字一般最多5个词语，封底文字一般最多25个词语。

Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.

youdao

前封面文字必须展示完整的标题，而标题的文字应当同等地显著可见。

The front cover must present the full title with all words of the title equally prominent and visible.

youdao

前封面文字最多可以包含5 个单词，后封面文字最多可以包含25 个单词。

Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.

youdao