I expect____(finish)the work by the end of next week I have something important____(tell)you

【专家解说】：现在理解你后面为什么提那个完成时的问题了： i expect to have finished=i expect that i will have finished将来完成时，用不定式替换了，强调“希望将来某一个时间之前（能够）完成”，不定式本身就可以有将来的蕴涵，所以后面一个用不定式to tell作为后置定语修饰something，“将来（在说话时间之后）告诉你”。