Previously I studied series, sequences, and convergence from the book A Text-Book of Convergence by W. L. Ferrar, and studying through this book was very good for me, because of the advantages that this book contains, and one of the most prominent of these advantages for me is the easy English langauge, and now I want to learn the basics of combinatorial analysis, so I want one book that is good for university students, and it must be simple in its language.
I tried to use the book A Walk Through Combinatorics - An Introduction to Enumeration and Graph Theory, it is very good but it is inappropriate for me because it does not have a simple language.
So I want your recommendation.