Do you just want to count how often each word appear? This would not be difficult and do not require any advanced algorithm.
But maybe you want to find some sequences of words that appear in many sentences? It that is the case, maybe you could extract the sequential patterns. For example, you may check this simple tutorial about how to extract sequential patterns from a Sherlock Holmes book using SPMF:
http://data-mining.philippe-fournier-viger.com/tutorial-how-to-discover-hidden-patterns-in-text-documents/Or maybe you could find other types of patterns.