许多现代工厂依赖各种机械装置来实现高效生产。
Many modern factories rely on various ___mechanical devices for efficient production.
他决定成为一名机械工程师,以设计创新机器。
He decided to become a ___mechanical engineer to design innovative machines.
飞机似乎因机械问题而坠毁。
The plane appears to have crashed because of a ___mechanical problem.