"The girl is eating rice."
Translation:Das Mädchen isst Reis.
Pressing alt+132 - ä - works for me, not sure if it works for everyone. Others are alt+148 - ö , alt+129 - ü , alt+225 - ß . Capitals are : alt+142 - Ä , alt+153 - Ö , alt+154 - Ü.
I have a list stuck above my PC with all the special characters for different languages - much quicker than pressing the button and if you use them often enough you can do it without having to look.
This should work in all Windows computers. Note that there's a second set of numbers that should work as well: Alt+0228 > ä, Alt+0246 > ö, Alt+0252 > ü. In both cases, you'll need to use your number keypad, not the numbers above your letter keys---welcome to the magical World of Windows.
If you ever forget the numbers, open Character Map (at least pre-Windows 8, should be in Program Files > Accessories, or possibly Accessories > System Tools, or you can just do Start > Run... > "charmap"). Once you find the character you want, look to the lower right corner of the window, and you should find a "Keystroke: " tip.
On Macs, it's much easier: press Option+u, then the letter to get the umlauted vowel; option+e, e for é, etc. I think ß is Option+s, but don't quote me on that.