The steepness of this mountain is a big challenge for climbers.

My horse is kept in that stable.

He took the horse to the stable.

This marathon is the best opportunity to test your endurance.

He made a romantic proposal of marriage to her.

He proposed to her in the park.

His sense of smell is very sharp.

I have been to Daegu.

He loves riding in a hot air balloon.

He saw ball lightning bouncing from the window.