On most if not all the international flights I've been on, the FAs will speak the language spoken in the departing/arriving country and definitely enough English to communicate clearly enough. Plus I'd be pretty sure they get the script in all the relevant languages they need.

Especially departing on a non-US carrier of a country where English is not the primary language, what language does the FA ask the passengers in if they can move the exit door? Maybe the FA for AF starts off with French, for instance, but when the passenger doesn't respond, it could be due to unwillingness or lack of language comprehension. Would there be a bias for the foreign country's language, in this case French, in deciding who can sit in the exit row?

Ex, On Air Canada TATL, I noticed the FAs with the drink/snack trolley asked all the passengers what kind of drink they wanted, in English. I asked one of the FAs how do they know everyone speaks English? Why not ask in French, or English and French, or with the other 2 languages announcements were made in?

I asked if they assess passenger language comprehension covertly, from the friendly greeting at the cabin door when boarding. American carrier FAs usually smile and nod, but AC FAs seem to try to have a short conversation in English with each passenger: "Hello sir. How are you?"

The FA said no, it's just a friendly greeting, and was surprised American carriers don't do that. Regarding the meal service, she said it's company policy is to assume the passenger knows English, and if that's not the case, bring over the FA who speaks their language.