For 参加, both characters are first tone, i.e. [cānjiā]. I can see that the entry for this word does not have the “listen” button, but you can hear its pronunciation by clicking the examples near the bottom of the page, or by pasting the word 参加 into the “voice” tab of “nciku mini help” floating near the bottom right of the page and then clicking “Listen to Pronunciation”.

Hello,

You would like to know how to pronounce 参加 in English? Okay :)

Yes, you are right it does mean "participate", which is pronounced (par-tis-eh-payt). If that does not help, here is the link from the website, just click the little button next to the word "participate" to hear it:

http://www.nciku.com/search/all/participate

Hope this helps!