他发现当他把嘴唇放在母亲的前额上，他就会让骨头以一种能让他母亲明白他说的话的方式运动。
He found that __________________________________________, he could make the bones move in __________ a__________ that she could understand what he was saying.
你就会发现某种值得思考的东西占据着你的头脑。
You will have __________________________________________ your mind.
正是这种对问题的探索造就了他那最著名的发明——1876年的电话。
___________________________________________his most famous invention—the telephone in 1876.
在探求改进电报的过程中, 贝尔发明了第一台电话机！
__________ the telegraph, Bell invented the first telephone!
贝尔完全懂得这项发明的重要性。
Bell __________ of his invention.
它十分稳定牢固，在桥梁设计领域的价值被证明难以估量。
__________, it has been proved invaluable in the design of bridges.