This old tunnel was once used in a mine.

He devoted his life to the study of morality.

This old tunnel was once a key point of transportation.

He traveled with me as a fellow pilgrim.

He found a large hollow in the mountain.

She is learning how to use adjectival nouns.

We have started a large-scale mobilization.

The movement of that robot is just like a human.

The reaction to his actions was strong.

I agree with his opinion.