Nope, you’re still not getting it.
"…but she also needs to know British usage"
Why do you think I linked to British newspapers’ style guides? :rolleyes:
Because you thought it would help. How, I’m not entirely sure, since American newspapers’ style guides are by no means indicative of how a majority of Americans speak or write.
But since it doesn’t seem as though we’re getting anywhere with each other, thoughts on something of a truce?
Alright, now I’ve had the final word 
Oh, do allow me to shut the door for you;)
I teach Maths, never Math