"Child labor" is, generally speaking, work for children that harms them or exploits them in some way (physically, mentally, morally, or by blocking access to education).
"Child labor" is illegal in Canada, but it is legal in the United States.
( z1 contrast :ARG1 ( z2 legal :polarity - :ARG1 ( z3 labor :ARG0 ( z4 child ) ) :location ( z5 country :name ( z6 name :op "Canada" ) ) ) :ARG2 ( z7 legal :ARG1 z3 :location ( z8 country :name ( z9 name :op "United" :op "States" ) ) ) )