Conversation one
对话一
W: One of the most interesting experiments with dolphins must be one done by Doctor Jarvis Bastian.What he tried to do was to teach a male dolphin called Bass and a female called Doris to communicate with each other across a solid barrier.
W: 最有趣的海豚实验之一一定是由贾维斯·巴斯蒂安博士做的。他试图教公海豚巴斯和母海豚桃瑞丝透过坚固的屏障交谈。
M: So how did he do it exactly?
M: 他具体是怎么做的？
W: Well, first of all, he kept the two dolphins together in the same tank and taught them to press levers whenever they saw a light. The levers were fitted to the side of the tank next to each other.
W: 首先他将两个海豚放在同一水槽中，教它们在看到光亮的时候按压杠杆。杠杆在挨着它们的水槽边上。如果灯光是时不时的闪烁几下，那么海豚应该按压左手边的杠杆，然后是右手边。如果灯光是持续的，那么海豚应该以相反的顺序按压。当他们回应正确时，就会有鱼作为奖励。
M: Sounds terribly complicated.
M: 听起来很复杂。
W: Well, that was the first stage. In the second stage, Doctor Bastian separated the dolphins into two tanks. They could still hear one another, but they couldn't actually see each other.
W: 这是第一步。第二步的时候，巴斯蒂安博士把海豚分到两个水槽。它们可以互相听到但不能看到彼此。
W:The levers and light were set up in exactly the same way except that this time it was only Doris who could see the light indicating which lever to press first. But in order to get their fish, both dolphins had to press the levers in the correct order.
W:杠杆和灯光的设置跟原来一样，不过这次只有桃瑞丝能看到灯光并按压杠杆。为了得到鱼吃，两只海豚都得以正确的顺序按压杠杆才行。
W:This meant of course that Doris had to tell Bass whether it was a flashing light or whether it was a steady light.
W:这就意味着桃瑞丝得告诉巴斯到底是闪烁的光还是持续的光。
M: So did it work?
M:那么管用吗？
W: Well, amazingly enough, the dolphins achieved a 100 % success rate.
W: 令人震惊的是，海豚的成功率是100%。
Questions 19 to 21 are based on the conversation you have just heard.
基于你听到的回答问题19至21。
Question19
问题19
What is the purpose of Doctor Jarvis Bastian's experiment?
贾维斯·巴斯蒂安博士做实验的目的是什么？
Question20
问题20
What were the dolphins supposed to do when they saw a steady light?
海豚看到持续光源的时候该怎么做？
Question21
问题21
How did the second stage of the experiment differ from the first stage?
实验的第二步与第一步的不同之处是什么？