He is living in a world of ignorance.

He was unconsciously humming the tune.

He is politically independent and has free thinking.

This yogurt is fat free.

This data was chosen at random.

This data was chosen completely at random.

I apologize for not contacting you for a long time.

He is so careless that he doesn't even take care of his own health.

He was completely indifferent to her feelings.

He is completely oblivious to his own talent.