Interview varies from post to post and depends on few factors. I think you are asking about Lecturership Interview. So here is some introduction about its interview:

For Lecturership interviews at SPSC, most of the times they ask candidates for demonstration of 3-4 minutes on any topic. Sometimes they give topic themselves and sometimes they leave all this on candidate's will. But it also depends upon the nature of the subjects specialist whether he/she wants to take Demo or not and from which part of the subject he like to have. To be in safer side you need to prepare 2,3 topics from your subjects so that you may be able to deliver short lecture over there.

Mostly committee for lecturership will comprise of three members (sometimes only two), out of which 1 member will be subject specialist. Specialist will only ask questions related to your subject, these may be token as well as conceptual. If the overall level of qualifiers is high then questioning becomes tough sometimes. After that one or two members of the SPSC will only ask questions related to General Knowledge, Islamiat, Pakistan Affairs, History of sindh, Every day science, current affairs etc. This is what you need to prepare for interview. Wish you best of luck.

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