Teacher:In this task, you're given a context, a sentence,  and a character. The sentence describes an action or job of the given character. Also, the context provides more information about the sentence or the character. Your task is to write the character's motivation by doing a specific job, which is given in the sentence. You can use context to find the motivation; however, all the inputs do not provide context. Also, in some inputs, there can be zero motivation; output, 'None' in this case.
Teacher: Now, understand the problem? Solve this instance: Context: Keine thought he was the best at picking the winning horse. One day he bet his entire mortgage on a horse who was sure to win. Keine's friend Joe bet against him. 
 Sentence: At the third leg of the race, Keine's horse had a heart attack. 
 Character: Keine
Student:
None