Get a book named PPSC Past Papers ( Latest Edition ) and get through it twice. This book will help you in G.K paper as well as in the papers of Pak Study and Islamiat objective portion. Apart from this book, get G.K capsule from Ilmi publishers along with EDS capsule and you will be good to go. For current affairs just search for recent events and make your own notes. G.K paper includes following portions.

1) Geography of the world
2) Knowledge about world Ogranization
3) Solar System
4) Basic knowledge about Science ( Physics, Chemistry and Biology )
5) Capital, Currency, Head of State etc
6) Knowledge about major incidents like WW1,WW2, Economic Crunches, Cold War etc.
7) Knowledge about famous International Personalities like Nelson Mandela, Gandhi, Mahateer Muhammad, Martin Luther Jr etc
8) Current affairs ( Recent Olymic, Different Summits held where and when, World Cups, Sports events etc
9) 1,2 question about sports as well like Thomas cup is for which sports?

Broadly, these topics are covered in G.K paper for PMS. No question related to Pak Affair or Islamiat is asked in G.K paper as there is a separate portion of 20 marks dedicated for MCQs in the respective papers.

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