Trained volunteers are collecting baseline data on water quality, and testing for selected suspected contaminants of the coral reef.
The volunteers must be interested in the water quality.
Trained volunteers are collecting baseline data on water quality, and testing for selected suspected contaminants of the coral reef. If they volunteered they must be interested which make it correct.
( z1 obligate :ARG2 ( z2 interest :ARG1 ( z3 person :ARG0-of ( z4 volunteer ) ) :ARG2 ( z5 quality :mod ( z6 water ) ) ) )