Analyze the following text.
Nicknames for coworkers
Kit Kat: always having a break.
Justin: Does justinuff not to get fired.
Butter knife: not the sharpest tool in the box.
Motion light: only works when someone walks past.
ET: just wants to go home.
Lantern: not very bright and has to be carried.
Blister: always shows up when the work is done.
(Available in: https://www.instagram.com/the.language.nerds/?hl=pt – text especially adapted for this text).
When the author says their coworker is "not the sharpest tool in the box" it means this person is: