We started an investigation into the incident.

The police are investigating the incident.

We need to conduct a factual investigation on this issue.

We went to the scene for fact-finding.

We conducted a questionnaire survey for the development of new products.

When will the next national census be conducted?

The next census will be conducted next year.

According to the latest public opinion poll, it has become clear that many people are in favor of environmental protection.

According to the latest public opinion poll, his approval rating is falling.

The Tax System Investigation Committee is discussing tax reform.