Rescue dogs with unknown histories may require more intensive—and thus more costly—training interventions initially.

https://docs.google.com/document/d/1wwsX4W8rVmZ-v_WNT1jLxPopUZO9tsVZpeR5Mfo3Tik/edit?usp=sharing

Rescue dogs with unknown histories may require more intensive—and thus more costly—training interventions initially.