Answer:
Yes, velocity can be negative. Remember that velocity is a vector quantity, meaning that it has both a magnitude, which is its speed quantity, and direction. Therefore, a negative velocity means that it is going in the opposite direction. Going in the opposite direction has to do with changing position to one lower than where you started.
For example, let's say we threw a projectile in the air. As it goes upwards, the velocity increases as it reaches the top, and finally at the top, its velocity is at zero. Now, because it's going downwards, the direction changed, and velocity is negative.