She had her menarche yesterday.

The police officer used a nightstick to restrain the criminal.

He is a keyboard warrior, he's not actually that strong.

He used clay to make a new mold.

Kei is my best friend.

The katsura is my favorite tree.

In English, adding 's' after a noun makes it a plural form.

He went to the police station and reported the theft.

He was calculating in his head.

He solved complex mathematical problems using his new calculator.