Unix forms the basis of many operating systems.

I learned how to calculate rational expressions in math class.

Free fatty acids are used as an energy source in the body.

My favorite skincare product contains bitter almond oil.

He is truly a person who embodies the saying, 'A man of virtue will naturally attract admirers.'

He is scheduled to have surgery on his bladder.

My sister is practicing the euphonium.

He is good at playing the euphonium.

Have you ever told her 'I love you' directly?

Euthanasia often becomes the subject of ethical debate.