Promises are scary things. To keep them means relinquishing some of our freedom；to break them means losing some of our integrity. Though we have to make them today, promises are all about tomorrow--and the only thing we know for sure about tomorrow is that we don't know anything for sure! And it's not just the outer world that changes in unforeseeable ways；it's you yourself. 每种新的体验--新的责任, 新的交往--都会使你的想法改变!
单词提示：
relinquishing v. 放弃 ; integrity n. 正直 ; unforeseeable 不可预见的
答案： Every new experience--new responsibilities, new contacts--changes your perspective.
本句节选自《The Power of a Promise》
总结：关于句中的几个词，对大家的回答做了以下统计。
体验，experience
责任，duty,responsibility,obligation
交往，communication,intercourse,association,contact
想法，mind,idea,perspective,opinion
以上的说法都可以表达出本句的意思。