Knowing when you are overflying something

Gig 601XL Builder writes:

Then I really have to ask, "Why in God's name did you ask the fraking
question?"

Because I may have to say "over XYZ" when reporting my position, or heed
instructions from ATC to "cross XYZ" and I wanted to know how to figure out
when I'm actually over something. I don't recall asking it in God's name,
however.

--
Transpose mxsmanic and gmail to reach me by e-mail.