"Run over and knock down" is a way to describe the action of crushing and knocking down something or someone with a vehicle.

The phrase "run over" means to drive a vehicle over something or someone, while "knock down" means to cause something or someone to fall to the ground or be knocked over by a force or impact.

Here are a few example sentences using these phrases:

"The driver lost control of the car and ran over the pedestrian, knocking them down to the ground."
"The depvery truck accidentally ran over the mailbox and knocked it down."
"The bulldozer was used to run over and knock down the old building to make way for the new construction."

In each of these examples, the action of "run over and knock down" is described as something that is done intentionally or unintentionally with a vehicle. The phrase is commonly used in the context of accidents or incidents involving vehicles.