In order to solve this problem, you need to understand the concept of the zero vector.

It's difficult to understand his explanation.

This concept is difficult.

He untied his shoelaces.

It took him a long time to solve the math problem.

This game is considered a zero-sum game.

Understanding vector fields is an important concept in physics.

A vector product is an operation that generates a new vector from two vectors.

It's difficult to understand his explanation.

The balance of his bank account is zero.