Pick up line recovery

A man is not stupid for not knowing something he was never taught. Could someone please explain what a vegetable is in the metaphorical sense

A vegetable (in a medical sense) is when someone is still alive, but completly un reacting to their environment. Basically, they're alive, but do not respond to the environment

I know I'm yet another guest, but you guys have amazing manners, and politeness.~
I respect y'all for that, and let your family know they did a fantastic job raising you! (v.v)
I'm glad there are people like you in the world~
Have a fantastic day!