A couple of months ago after my first solo x-country flight in
Italy I did use English phraseology for practice, which is not really appreciated by ATCOs as I increase their workload.
After landing TWR came over with the following:
"I-IABS on ground at xx..ehm are you a military pilot?"
"Ehm.. on ground at xx ... and negative just a student!!"
I had a good laugh and did smile for some time. (had only 17 flight hours at the time)