This textbook series may have 10-12 volumes
4 volumes for beginner level: a total of 42 lessons (included 2 lessons for pronunciation) , beginner level will only focus on Spoken Cantonese
4 volumes for intermediate level: a total of 40 lessons, intermediate level will touch the complex sentences and a little a Written Cantonese
2-4 volumes for advance level: start teaching formal expression of both Spoken and Written Cantonese

*This is only a preliminary plan; the final publication will be adjusted based on circumstances.