work at/on

上面两个句子在意义上并没有什么区别。只是 work at 仅仅用于英国英语，而 work on 则既用于美国英语，又用于英国英语。

She is working $\$left\{\begin{array}{l}\text {on(AmE)(BrE)}\\ \text {at(BrE)}\end{array}\right\} her new play. (CGEL) 她正在努力写她的新剧本。

1. He's working at a new invention. (Palmer) 他正在努力搞一项新发明。

2. We were working on a new generator. (Cronin) 我们正在研究一种新的发电机。