checking of solution

例句：

1. 1.The engineer was checking the new machine before it was put into use.
   工程师在机器投入使用前正在检查它。
2. 2. The teacher is checking the homework for the next class.
   老师正在批改下节课的作业。
3. 3. The company is conducting a thorough checking of its financial records.
   公司正在彻底审查其财务记录。