(2) A substantial percentage of pregnant adolescents either abuse substances by experimenting with alcohol and drugs or live in an environment in which substance abuse occurs and thus are at risk of exposing their infants to dangerous and harmful substances.
(substance abuse; occurs; L:an environment) (substance abuse; are; at risk of exposing their infants to dangerous and harmful substances)
substance abuse substance abuse
occurs are
L:an environment
at risk of exposing their infants to dangerous and harmful substances