英语语法分析

When Johanson and his colleagues discovered Lucy's partial skeleton in 1974, it showed that she walked upright, confirming that our ancestors did so before their brains started getting larger.

当Johanson和他的同事在1974年发现Lucy的部分骨架时，他们发现Lucy是直立行走的，证实了我们的祖先在大脑容量开始变大之前就已经可以直立行走了。