He is spending a lot of time on experimental research.

Well then, I'm off.

He admitted that it is difficult to execute the plan, saying 'it is easier said than done.'

He is majoring in Japanology.

He is deeply interested in Zen studies.

My major is oceanography.

He is an expert in enzymology and has conducted many studies in that field.

He is writing a thesis on phenomenology.

He is an expert in serology, working on research into infectious diseases.

He is interested in toponymy.