Complex sentence: The PPQ program attempts to safeguard agriculture and natural resources in the United States of America against the entry, establishment, and spread of animal and plant pests and noxious weeds to ensure an abundant, high-quality, and varied food supply.
Split into simpler sentences: The PPQ program works to safeguard agriculture and natural resources in the United States of America against the entry, establishment, and spread of animal and plant pests and noxious weeds. PPQ's goal in doing so is to ensure an abundant, high-quality, and varied food supply.