Ask, talk, observe and test on site, consult relevant records and obtain external information. On-site investigation methods include:

1, interview survey method: visitors directly ask the interviewee how to understand the social situation or explore social problems through oral conversation;

2. Observation and investigation method: the method that investigators directly perceive social phenomena in the natural state by using their own sensory organs or with the help of scientific observation tools according to the purpose of investigation, and observe and test them on the spot;

3. Research methods in real social life situations.