Pronounceable Initials

All syllables below are pronounced as first tones.
The syllables in each row are read one by one from left to right.
The characters are for reference only.
The vowels following the consonant initials for reading and memorizing are conventionally so.
Initials are grouped this way because sounds in the first three rows are relatively easy to discern,
whereas sounds in rows 4 - 6 are very confusing to some learners.