He was studying ancient documents and found the character '黃門'.

His specialty is computer science.

He sneaked into the school through the back gate.

This sluicegate is used to regulate the water level of the river.

This organism is classified into the subphylum.

I went to see the Arc de Triomphe in Paris.

He is deeply studying about the classification of superphylum in his biological research.

A baby's fontanelle naturally closes a few months after birth.

A baby's fontanelle closes a few months after birth.

This book explains in detail how to use the 'Kyūjitai form of 声門' in old Japanese.