When I went for my interview back in 2003 (it was unsuccessful), I wasn't asked to read any script. I was shown a picture. A picture of a man flying first-class enjoying being served by one of the flight attendants offering him drinks and food. I was asked to speak about the picture in Mandarin and that was all. They didn't even try and speak to me in Mandarin. My guess is the woman who was interviewing me could understand Mandarin and she couldn't actually speak it. A bit like my Cantonese.