I think in backwards English, and I have for decades. I may have started in elementary school. I’m not sure precisely why I started developing backwards English. I say “develop” because there is a whole system of rules that I’ve devised and occasionally still modify. For example:
The emphasis is always on the same syllable that’s emphasized in standard English.
The ending -tion (as in salvation or conniption) is pronounced “noyt”; there is no “sh” sound.
I never say God backwards and I never say dog backwards. Bad words to mix up.
I use the word “oy” instead of the word “I.”
The sound “ch” is pronounced like the letter “kha” in Arabic, or like the Hebrew kha in “chanukah.” So “speech” is pronounced “kheeps.” “Sh” is pronounced “zh.”
I usually don’t translate proper names or foreign words backwards.
There are other rules but I won’t list every single one here lest I interrupt the time you need to digest the fact that I do this at all.
Everywhere I go I translate things into backwards English in my head. So if I pass a sign that says “Exit 34” in my head I think “tizgeh etrit ruof.” That’s the best transliteration I can do. Recently I started speaking backwards English aloud (when I’m alone) to see how it sounds. It’s surprisingly hard to speak even though it’s the language I think in.
Now if you’re ever asked a trivia question about me you can answer correctly.