Engineers have built-|||-robots that have one or two of these abilities.But it takes a number of big expensive-|||-computers (6) __ (make) the robots work.-|||-The(7) __ (big)problem in creating a human-like robot is copying human-|||-intelligence. The way the human mind works is almost impossible to copy.A simple-|||-computer (8) __ do mathematical problems far beyond the ability of even the-|||-smartest human mind.But the human mind is better than a thousand supercomputers-|||-(9) __ speaking, hearing andproblem-solving. Several American and Japanese-|||-companies are working (10) __ (develop)the senses of sight and touch for robots.-|||-The development of these senses will make robots much more useful.-|||-However,the most important human ability -the most difficult to copy - is-|||-promem-somen an methern gro mot must be able to change the way it acts-|||-(11) __ it faces an unexpected sination. Huma do it all the time. Computers-|||-must do it for robots. This means computers must have a huge base of information about-|||-many things. They must be able to find quickly the(12) __ (need)information in-|||-their systems. And they must make choices about how to act. So far,this is beyond the-|||-ability of computers.