His theory is very interesting.

I love nature.

This park is very rich in nature.

He naturally demonstrated leadership.

He worked late into the night to complete his doctoral thesis.

I plan to write a short essay tonight.

It's difficult to remember the stroke order of kanji.

He picked up a pen to write down the poem.

He is an expert in embryology, studying the developmental processes of many kinds of organisms.

The process of embryogenesis is very complex, with continuous cell division and differentiation.