This has big “the horrors persist but so do I” energy. I love it

I posit this completely made up definition.

Shark is an adjunction of two words

Sharp; because, well look at them

and Ark; because they are boats.

Sharp-Ark > Shark

Isn’t language funny sometimes

Once they have been filled once they are never truly empty.

Even then, it’s much safer to assume they are full than gambling on them being empty. Dangerous goods transport regulations don’t differentiate for a reason

The best way to validate an email address is to sent it an email validation link.

Anything outside of that is a waste of effort.