This is the pen that I lost.

Translation language

Sentence

Narrator

If you lose a pen, try to retrace your steps to find it.

I'm always losing pens; this is the latest one.

Have you ever lost a pen you really liked?

If I hadn't lost this pen, I could have finished my notes.

This pen is the one I misplaced.

This is the pen I lost, bummer.

I lost this pen.

Misplaced or no longer in possession of a pen.