Restore: Language Bar missing in Windows 8.1
Sometimes, even after enabling language bar in your Windows Control Panel, you may find that the Language bar is missing. It may disappear completely and become visible only when UAC prompts to switch to administrator account. The possible reason for this problem could be addition of just a single language as an input language.
Remember, Language bar will be displayed either on taskbar or desktop, only when you select more than one language as input language. Be sure your second language is listed in the input language list. If not you can add it by pressing Add button to add another language.
If you find that your Language Bar is still missing, here is what you may try.
Language Bar missing
In Windows 7 , open Registry Editor and navigate to the following key:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
Check for a string parameter named CTFMon. If it exists, ensure that its path is set to C:\Windows\system32\ctfmon.exe. If not create this String Value. Restart your computer.
Now click on the Language Bar icon that you will now on the taskbar and select Show the Language bar.
To hide the Language bar, select Close the Language bar.
You can also control the behavior of the Language bar via the Control Panel > Region & Language > Keyboards & Languages tab > Change keyboards > Language bar tab.
Things have changed a bit in Windows 8 and Windows 8.1. While the registry key and method still holds true, when you click on ENG, you will see the following pop up.

Click on Language preferences. In the left side select Advanced Settings and then Change language bar hot keys. You will see the settings under the Language bar tab.

Under the Advanced settings, you will also see a checkbox for Use the desktop language bar when it's available.
Hope the changes made in Windows 8, Windows 8.1 are clear.