He has developed a writer's callus on his hand because he writes for long hours every day.

I draw my eyebrows using an eyebrow pencil.

We will use pentane in this chemistry experiment.

My new pen tablet is very easy to use.

My new fountain pen is easy to write with.

I lost my mechanical pencil, so I'm going to buy a new one.

He was writing a letter with an old-fashioned quill pen.

Propene plays an important role in organic chemistry.

I used pentyne in an organic chemistry experiment.

We prioritize customer satisfaction above all else.