1、Police have launched an investigation into the incident.
警方已对这起事件展开调查。
2、The company hired a private investigator to conduct an investigation into the employee's misconduct.
公司聘请了一名私家侦探对员工的不当行为进行调查。
3、The journalist conducted a thorough investigation to uncover the truth behind the scandal.
记者进行了彻底的调查，以揭露丑闻背后的真相。