The Sunday Times Jumbo General Knowledge Crossword Book 7: 50 general knowledge crosswords (The Sunday Times Puzzle Books)Test your general knowledge with these fiendish crosswords. A jumbo crossword puzzle and general knowledge workout to test and stimulate the brain cells with 50 large grid puzzles from The Sunday Times. These puzzles use a 21 x 21 jumbo size grid, and appeared in the pages of the Sunday Times, they offer an entertaining and stimulating challenge to all crossword lovers and anyone interested in quizzes, trivia and testing their all round knowledge.