The West African Examinations Council (WAEC) occasionally publishes past question booklets for purchase. These are the most authentic sources.
Simple, compound, and complex sentences in Twi. twi bece past questions and answers
While past questions are invaluable, they are most effective when used alongside the official WAEC BECE syllabus. The syllabus outlines all the topics you are expected to cover for the examination. twi bece past questions and answers