几个英语句子翻译.（补充如下）
1. What if we take similar European and American metropolitan areas and adjust for human capital and hours worked?
2. The fractious, class-riven European continent struggled to copy this technology, and while adoption of these methods eventually led to a period of rapid catch-up growth, the process of catch-up was never quite completed. and so that is a gap to explore.
(重点fractious 跟 class-riven 该怎么翻译,还有最后一句)