Cows

A: "There's a flock of cows over there"
B: "Herd of cows"
A: "Of course I've heard of cows, there's a flock of them over there!"

It's an old joke, which probably works better in speech than in writing - or maybe not at all.

Anyway, I saw a nice group of cows whilst out walking the dogs this afternoon.

I had a disturbing senior moment this afternoon; having driven to the park with the dogs, I then walked home, stood outside the house for a moment wondering where the car was, before realising that I'd left it at the park!
Sad, I know.