How to stop gnome terminal 2.16.0 suddenly switching to Japanese input
 

There are many threads about how to input in Japanese.
I have the opposite problem. My installation is RedHat 5,
64 bit. I use gnome terminal 2.16.0 on a gnome desktop.
Every once in a while, while typing, my finger slips and
I hit some unknown key, perhaps a function key? and suddenly
my subsequent input turns into Japanese characters (not Chinese,
I know the difference). Anybody know how to change it back
to whatever the default English mode is?
I tried checking all the menus at the top of the terminal
window, also the Keyboard Indicator 2.16.0.1 that I have on
my control panel, but the keyboard preferences there is
already set to U.S. English, so it seems the gnome terminal
is not looking at this. The only thing that works is to
kill the terminal and start a new one.
Thanks,
gnreeke

If you're getting full Japanese input, and it's not just an improper keyboard mapping, then you have to be running some kind of IME. This is most probably scim or uim, in which case you should also have an icon in your system tray for it, or a floating toolbar or something in which to access it.

I believe the default toggle switch for most of these systems is shift+space, or perhaps ctrl+space, but it could be different depending on your settings. If you're using scim and can't find an icon for it, you can run scim-setup to get the settings control panel, where you can confirm/change the global trigger hotkey. Not sure what you'd need to do if you're using something else.

Now that is a question I don't think I've ever seen ;)

To fix the symptom and not the problem, you could just type in reset, as opposed to restarting the thing, but as David the H. shift+space is usually the switch for this

How to stop gnome terminal 2.16.0 suddenly switching to Japanese input
 

Thanks esp to David the H.
scim is indeed running; I was just not familiar with it.
scim-setup tells me that Ctrl-Space is indeed the toggle character,
and typing it brings up a little window that tells me the input is
English/European. The Ctrl-Alt keys that are supposed to change the
input method don't do that, instead they change workspaces. Both
English and Japanese input are shown as being enabled. Since I
don't need Japanese input, I just unclicked the enable button on
the Japanese and clicked APPLY. Hopefully this will cure the
problem for good, but if it doesn't, I will post to this thread
again.
gnreeke