AOA Dear Bro!
I am also an aspirant of 2014 so i keep on checking different Threads on the same forum in which some are really helpful.n
Anyways according to my personal experience the undermentioned books are really really very good...
High School English Grammar & Composition by Wren and Martin
Active and Passive Voice Made Easy by Efzal Anware
Direct and Indirect Speech Made Easy by Afzal Anware
all these books are great

i have also came to know from this forum that Exploring the World of English Syed Saadat is good for Precis and Essay Writing, although i have tried it yet but thinking to go for it

There are also very useful suggestions @ Pakistani Guy, I am going to sum up his words
@ Pakistani Guy
Current English Intermediate part I and part II by Sir Mumtaz, Punjab Board, Urdu Bazar Lahore are the two books for sentence correction. You can easily cover sentence correction of CSS exam by going through these books. I have evenchecked past papers of CSS. Many questions were same in CSS papers which I also noticed in these books. There are 30 exercises of sentences correction in Current English Part-II book.

Then Efzal Anware Mufti's book Direct and Indirect Speech Made Easy is good enough for the preparation of Narration in CSS exam.

Then, Rabia Series, Art of Precis Writing is excellent book for preparation of precis writing.
Then, Syndery reflection is a good book for explanation of ideas.

Another thing please do not over do in just choosing books made the decision early and go for that ...
Good Luck

Regards
Sara

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