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.