Instructions: You are given two sentences. You have to find if there is entailment or agreement of the Hypothesis by the Premise. From the given pair of sentences, you should identify if there is enough information in the Premise to support the claim made in the Hypothesis. The Premise may not exactly be the same as Hypothesis. Your task is to return 'entails' if the premise supports hypothesis else return 'neutral'.
Input: Premise: There are four valves, composed of dense connective tissue covered by endothelium, which prevent backflow of blood in the heart's blood path by opening and closing relative to pressure changes. 
 Hypothesis: Heart valves prevent the backflow of blood from happening in the heart.
Output:
entails