She piggy-backed her little sister across the playground.

She gave her little brother a piggy-back ride.

She carried her little brother piggy-back across the field.

She piggy-backs her little sister when they play.

She gave her little brother a piggy-back ride.

Back engineering is the process of analyzing and understanding the design and functionality of a product by examining its structure and components.

Back-engineering is a common practice in the field of software development.

The company back-engineers their products to improve performance.

They were able to back-engineer the software and figure out how it worked.

Scientists back-engineered the alien technology to understand its functionality.