>>735164
>masha'Allah
We do, but 1) not in that dialect (ie we say mashallah instead of masha'Allah) and 2) we rarely say it. Very rarely.
>alhamdulillah
We do, but not in that form. Instead of saying Alhamdulilah, we say hamdillah, which means the same thing.
We do NOT say Allahuakbar, despite what some Muslim twitter users tell you to appeal to us. We do not.
>What are some uniquely Christian Arabic language expressions?
Well, it differs for each dialect/country. In Lebanon, we say "smissalib", short for "biesm assalib", which translates to "In the name of the Cross". We do so when we are frightened, scared, surprised (in a "scary" way), when we bless someone. among other things.
We also say sometimes "ya adra", which translates to "Oh Virgin", an obvious reference to Virgin Mary. "Ya Yasou3 (the 3 is )", which translates "Oh Jesus". We usually say these things when we sit down in a tired fashion, when we are mentally tired, frustrated, joyous, among other things.
So far, these are the only things I can think of at the top of my head. Also, as I said these expressions differ in each country. Copts possibly have different expressions, Palestinian Christians the same, and so forth.