遗赠扶养协议是什么
遗赠扶养协议，是指遗赠人与扶养人签订的由扶养人承担遗赠人的生养死葬的义务，遗赠人于死亡后，将约定遗产转移给扶养人的协议。
通俗的说，就说张三和李四签订合同，约定张三给李四养老送终，李四死后，李四的财产归张三。
错误的中文翻译
国内的译者将遗赠扶养协议译为 legacy-support agreement，参见厦大法学院何丽新教授的文章，以及《遗赠扶养协议中的利益失衡及矫治》的英文摘要部分。
然而，在英美法中，legacy support agreement 另有所指，通常是指软硬件的维护支持合同。和遗赠扶养协议完全无关。
In CA, Inc. v. Ingres Corp., 2009 WL 4575009, CA spun off Ingres as an independent software company. To accommodate the remaining CA customers who would continue using software now controlled by Ingres, the parties entered into a "Legacy Support Agreement," which provided for Ingres to maintain and support the software for CA's customers.
此外，legacy-support agreement 在谷歌的精确检索结果只有108个，且多数来自非英语国家（大部分是中国），说明这在英文中是个伪概念。英语母语人士并不会使用这个词来表示遗赠扶养协议。
英文翻译参考
如果要用英文解释遗赠扶养协议的概念，大致如下：
It's a legal contract where one party provides care and support to another party, and in return, they are designated to inherit the estate of the party receiving care upon their passing.
根据这篇文章，这一类的合同在英文中是 personal care agreement 或者 caregiver contract。