I have been to Chicago.

The Paleogene period was a very important time in the history of the Earth.

The cytosol is the liquid part inside the cell, and many enzymatic reactions occur here.

His son is undergoing treatment for blastoma.

His son underwent surgery for blastoma.

He was walking along the beach wearing a straw hat.

My four treasures of the study are a fountain pen, a pencil, an eraser, and a ruler.

He wrote a poem using the four treasures of the study.

He was wearing a straw hat to avoid the summer sun.

He wore a fedora and looked very stylish.