potential主要是“潜能”的意思。
例句：
It recognizes that every child has limitless potential for success and limitless capacity for love. 每一个孩子都成功的无限潜力、都有爱的无限能力，这是公认的。
prospective主要是：“预期，展望”，“预期的，未来的”
例句：
She is married to a prospective lawyer.
她嫁给了一个未来的律师。
She is his prospective mother-in-law.
她是他未来的岳母。
参考资料：灵格斯，有道