The government's reluctance to step in contributed to the reluctance of other banks to strike a deal with the troubled company.
The government reportedly helped AIG in order to prevent a bankruptcy that would have had broad implications for the U.S. and global markets. By comparison, the Lehman fallout was seen as more contained.
我的问题是:step in contributed不是应该是step in contributing吗,怎么是过去式呢?还有给帮忙翻译一下这两个句子,