Subvocals are those sounds in which the vocalized breath is more or less
obstructed.
Aspirates consist of breath only, modified by the vocal organs.
Words ending with subvocal sounds may be selected for practice on the
subvocals; words beginning or ending with aspirate sounds may be used for
practice on aspirates. Pronounce these words forcibly and distinctly,
several times in succession; then drop the other sounds, and repeat the
subvocals and aspirates alone. Let the class repeat the words and
elements, at first, in concert; then separately.