What are the qualities of a good text book?

Answer 1

The book contains learner-centered materials and content.
The book contains teacher-friendly instructions and reference material.
Principles of effective ESL instruction are the basis for format, context, and
design (including art work, layout, font style/size etc.).
Language skills are incorporated throughout instruction.
Principles of adult education are implemented in lesson format, context, and
design.
The textbook series is affordable and can be used as a non-disposable
resource if possible.