Most people think of computers as very modern inventions, products of our new technological age, (25)______ actually the idea for a computer had been worked out over two centuries ago by Charles Babbage (26)______ was born in 1791 and grew up to be a brilliant mathematician. He drew up plans for several (27)______ machines which he called "engines". But despite the fact that he started building some of these, he never finished any of them. Over the years people have argued whether his machines would ever work. Recently, however, the Science Museum in London has finished building an engine based on one of Babbage's designs. It has taken six years (28)______and more than four thousand parts have been specially made . Whether it works or not, the machine will be on show at a special exhibition in the Science Museum to remind people of Babbage's work. Question 25: A. and B. but C. so D. however Question 26: A. who B. which C. whose D. when Question 27: A. caculator B.caculated C. caculating D. caculates Question 28: A. to complete B. completing C. completed D. complete