Understanding the part of speech is essential for learning grammar.

The passage of arms between the two nobles lasted for years.

He filed a patent application at the patent office.

I brought her a bouquet of flowers as a peace offering .

He is a peer of the realm.

I accidentally spilled hydrogen peroxide on my clothes.

The petty officer is responsible for maintaining discipline among the crew.

The petty officer first class is responsible for supervising and training junior enlisted personnel.

The petty officer second class is responsible for training and supervising junior enlisted personnel.

He was promoted to petty officer third class.