题目

Today there are already robots working in factories. Some can help to build cars, and they do simple jobs over and over again. Fewer people will do such 1． in the future, because they are boring, but robots will 2． get bored. Scientists are now trying to make robots look like humans and do the same things as we do. However, some scientists believe that although we can make robots move like people, it will be hard to 3． them really think like a human. For example, scientist James White thinks that robots will never be able to 4． up and know where they are. But many scientists 5关于晶体和非晶体的熔化，下面说法中错误的是（      ）A．晶体有熔点，非晶体没有熔点B．晶体熔化时温度不变，凝固时温度也不变C．非晶体熔化时，是由固态变成液态D．熔化时吸热不断升温的固体一定是晶体