I often hang out with my underclassman at school.

I need to buy new underclothes.

She folded her underclothing neatly and placed it in the drawer.

The undercoat of the animal's fur keeps it warm in cold weather.

I accidentally undercook the chicken and it was still pink in the middle.

He worked as an undercover agent to gather information.

The undercurrent in the river was strong and dangerous.

The store undercut its competitors by offering lower prices.

Many underdeveloped countries struggle with poverty and lack of resources.

The underdog team surprised everyone by winning the championship.