He was hiding the fact that he was an illegitimate child.

The ecosystem of zoobenthos is an important field of study in marine biology.

The study of benthos is an important field in marine biology.

Phytobenthos is an important part of the marine ecosystem.

He is interested in geometrical shapes.

He is conducting research on historical kana usage.

He often thinks about problems from a humanitarian perspective.

His company is facing the risk of a hostile takeover.

He is spending a lot of time on experimental research.

That plan is too impractical, it's difficult to implement.