He spent time on the revision of the thesis.

He looked over my report for me.

He made several revisions to my report.

This hotel has a natural hot spring.

He explained the full story of the incident in detail.

The Japanese oak silkmoth is a moth unique to Japan, characterized by its beautiful patterns.

This dress is made of tensan silk.

This beautiful gem is a natural product.

Smallpox is a disease that caused a lot of suffering in the past.

When you transpose a matrix, the rows and columns are swapped.