主修机械英语翻译

My major is Mechanical Engineering. 这个在文书里用比较好I'm a Mechanical Engineering major. 这个就比较口语化

该题看不到问题补充，不适合高质量回答，建议收回。

I'm responsible for repairing the engines.

这和时态是两回事。。。和语态好像也是两回事。。。貌似叫什么非谓语动词。。。因为I am an engineer majoring(majored) in Mechanical Engineering.等同于I am an engineer ,and I am majoring in Mechanical Engineering.合并为一句话用majoring......去看看高中语法书。。。肯定有。。。

应该用majoring 如果想要表达曾经主修机械工程的话可以这么写：I am an engineer who majored in mechanical engineering

I major in mechanical specialty in the university