Sandbags

The soldiers filled the sandbags with sand.

Sandbags can be used to erect a temporary wall to protect against floods.

Get to work. These sandbags won't fill themselves.

They made the sandbags heavier.

Three sandbags have fallen out of the truck and spread on the road.

Thousands of emergency workers and volunteers worked through the night to stack sandbags around the city's restored center, which boasts architectural gems.

What are these sandbags used for?