My classmate said that the word "wastes" should be read with the "tes" at the end dropped, like "weis".
However, my teachers usually read the word like "weists" or "weis:s".
This confuses me a little bit and I can't check out the actual pronunciation of the word anywhere. Hope anyone who knows the exact pronuncation of the word can help solve the problem.
Thanks for everyone's answer.
I was a little unsure because my classmate insisted on his pronunciation and said that he learnt that from BBC.com. I tried looking up the dictionary to decide who's right but couldn't find a situation similar to the one in this case.
Thanks again to everyone.