re-Created LMGi, Lessons 2a and 2b

I am learning how to create 2 compositions on one page in Lilypond, and I used a very complicated method so far. But found a much simpler solution and quickly created the content for LMGi, Lessons 2a and 2b.

LMG-02a+02b-guitar,ukulele.pdf LMG-02a+02b-guitar,ukulele.pdf
LMG-02a+02b-leadsheet.pdf LMG-02a+02b-leadsheet.pdf
LMG-02a+02b-piano.pdf LMG-02a+02b-piano.pdf
LMG-02a+02b-recorder.pdf LMG-02a+02b-recorder.pdf