He has psychopathy, making it difficult for him to understand social rules.

He was confined to his sickbed for a long time.

I have a severe headache due to meteoropathy.

He suddenly fell ill and was taken to the hospital.

He suddenly fell ill.

If you don't get regular dental check-ups, you may develop periodontitis.

My grandfather is suffering from Parkinson's disease.

He is suffering from an incurable disease.

The pulse width of the laser is measured in picoseconds.

This light bulb consumes one watt-second of energy per second.