He is learning Ancient Greek language.

Old Church Slavonic is the oldest recorded language of the Slavic group.

Old Church Slavonic is the first language written by the Slavs.

The characteristic of annelids is that their bodies are divided into ring-shaped segments.

This butterfly valve is used to control the flow of fluid.

He explained in detail about the structure of the sphenoid bone.

He drew a straight line using a T-square.

She is learning the grammar of the present progressive form.

This shape is a parallelogram.

This shape is a parallelogram.