HI guys: Suppose I want to tell certain websites to come up speakingI know of no way to do this. If I remember correctly, it should work the other way around. If (1) the web site in question has the properly coded language tags in its HTML code, (2) you're using a multilingual synthesizer that supports the language in question, and (3) you've got language detection turned on in the settings center, JAWS should automatically switch to that language and read the web page in that language.
Turning language detection on is easy with JAWS 12 or higher. Press insert+6 to go into settings center and type "language" in the search box, then press enter. In the search results list, you'll see an item labeled "Language detection". If it's not turned on, its checkbox will be unchecked; just hit the space bar to turn it on, tab to Apply, then tab to OK and press enter.
Hope that helps.