Learn German: Sie verfasst das Kapitel, während er das Buch liest. - She is writing the chapter while he reads the book.

The verb verfassen specifically means to compose or author a text, like an article, chapter, or book. The word schreiben is the general term for writing, which could just refer to the physical act of writing letters on a page. At a B2 level, using verfassen sounds much more professional and precise for literary or academic contexts.

Why is the verb liest at the very end of the sentence?

The word während (while) acts as a subordinating conjunction here. It introduces a dependent clause, which always forces the conjugated verb (liest) to the very end of that clause.

How could we rewrite 'the chapter that must be written' to practice the Gerundivum from this lesson?

You would use zu plus the present participle (verfassend) and an adjective ending. Because Kapitel is neuter and follows the definite article das, we add the weak ending -e. This gives us the attributive passive phrase das zu verfassende Kapitel (the chapter to be written).

If we wanted to describe the book as 'the book to be read', how would we form that?