ii
Hyphens can also join
adjectives, where there are two of the same type in a row:
e.g.
low-amplitude (compound adjective),
thermo-acoustic (compound adjective) energy (noun)
Note that whilst
amplitude, for example, can be used as a noun, in this context, it is being used as an djective. In each pair, the two adjectives or
classifiers are strongly linked, giving pairs of single concept adjectives or
classifiers, hence the hyphen to show that there are two pairs of
adjectives not four, solo
adjectives.