For example, the fields of Western farmers feed the United States and many other parts of the world, and India's irrigation systems have enabled that country to be self-sufficient in food production since 1974. In addition, in many parts of the world dams have helped to remedy life-threatening problems such as poverty from lack of economic development, famine as a result of drought, devastation from floods, and continued disease from lack of potable water supplies.
Farmers grow food to keep people fed 
( z1 grow :ARG0 ( z2 person :ARG0-of ( z3 farm ) ) :ARG1 ( z4 food ) :purpose ( z5 keep :ARG0 z2 :ARG1 ( z6 feed :ARG2 ( z7 person ) ) ) )