SORU: boşluğa uygun düşen cümleyi bulunuz
Would-be inventors have long dreamed of creating a machine so efficient that once started, it would keep itself going indefinitely with no consumption of fuel or other natural resources. ........ . It would also make the inventor very rich and put today's electric and oil companies out of business. The story of the quest began at the dawn of civilisation and, for some, still continues today.