the exercises, we went on to learn the new words in the next unit.
A. Finished
B. To finish
C. Having finished
D. Finishing
网友回答
A. Finished
B. To finish
(答案→)C. Having finished
D. Finishing
解析：句意：完成练习后，我们继续学习下个单元的生词。因为是先完成练习，然后才开始学习新单元的单词，所以表示先于主句的谓语动词的状语，用现在分词的完成式，选C。