Guys I don't think language is problem.
I think it's Bing. Bing is nothing more than third class boring search engine if you are not in USA.
So, if you ask cortana lets say weather reports it can't answer it because bing simple shows weather websites.
In my opinion bing is the real problem here and MS have to improve it before they lauch Cortana globally.
Now, whom to blame for bing services,
I think we all know whom
Yep. Exactly. This has already been mentioned a few times.
The only people who think speech recognition support for non-English speakers is the biggest problem, are those who have never seen TellMe working on a non-English smartphone (since WP7 Mango, and in many other products long before that).
Speech recognition is a very difficult problem to solve, but it has been a focus of computer research for well over three decades now, in which MS has always been heavily involved. It is also a problem that has a very generalized solution. MS doesn't need a Cortana specific speech recognition engine. Speech recognition is speech recognition... it works the same everywhere, for all services. The problem today is more related to what happens after speech recognition:
Once the speech recognition engine determines that the user said:
"What time will my aunt's flight arrive in London"
the digital assistant must figure out how to answer that question.
First it must determine which flight the user is referring too, which requires that the digital assistant understand family relations in general. It must then determine which of your aunts you may be referring to and which of them may be on a flight headed towards London, presently or in the near future. That task may be even more difficult if you call a long time family friend an aunt, which isn't strictly related by blood. Then the digital assistant must be able to look up flight information for any given airline and any given airport, including information about delayed flights, which will work differently in different countries. It must then make a distinction between local time and your current time (if you are not in the same time zone as London). Finally, the digital assistant also needs a way to present that information graphically and provide a synthesized verbal response that makes sense for flight information.
All that just to answer a single question about flights. That is what Bing is eventually intended to do, but answering such questions
requires the ability to integrate and query data from a whole range of national data sources. Bing in the U.S. is far closer to that goal. Outside the U.S. Bing is not even remotely close.
That is the problem.