字典解释

“instrumental”来自名词 “instrument”（乐器），除了表示与乐器演奏有关的意思外，它还常用来表示“有帮助的” “起作用的”。我们很多时候都可以用它来替换 helpful，play an important role 等表达。

我们常说“细节决定成败”，说的是细节的重要性，我们可以表述为：
Details are instrumental in achieving success.

当别人对我们有所帮助，我们在写邮件和卡片的时候就可以用上 instrumental。比如流行小说 Crazy Rich Asians 的作者在书尾鸣谢部分就用到了 instrumental：
In your inimitable and wonderful ways, you have each been instrumental in helping me bring this book to life.

例句

In China, for example, Jackie Chan, a firm star who was instrumental in bringing about that country’s recent ban on the sale of elephant ivory, has thrown his weight behind the pangolin(穿山甲).

翻译练习

教育改变了我的命运
Education is instrumental in changing my life.

参考翻译：
Education has been highly instrumental in transforming my life.

或

Education is an instrumental tool in shaping my destiny.