Unlike his parents, the young boy seemed not to be glad to see the cows every morning.

Aristotle examines the concepts of substance and essence (ousia) in his Metaphysics (Book VII), and he concludes that a particular substance is just a matter or a form.

To his father, milking cows was a complicated job.

The author always milked the cows alone in the barnyard.

The author’s father milked the cows because they needed to be milked.