What is it called when a police officer slows on the freeway

Also known as “rolling roadblocks,” a traffic break is a separation within the traffic flow, on a highway. ... Essentially, a traffic break is the creation of traffic separation by a traffic patrol officer slowly swerving back and forth across all lanes of a highway, not allowing other vehicles to pass.

What the question i don't get it do u mean what she needs to do to auctually become one