Complete the following sentence with a (compound) word derived from the one given in bracket.
So many people exhaust their health gaining wealth, and then have to spend their wealth to（ ）their health. (gain)
【正确答案】：REGAIN
【题目解析】：
本题考查常见动词的衍生动词。
分析语境，太多的人消耗自己的健康来获取财富，然后他们又不得不花费金钱来...健康。由不定式标志to可知，空缺处应填动词原形，而前句已出现gain，那么此处含义应为“重新获得、恢复”，gain作动词意为“获得”，加上前缀re-变成regain意为“恢复”，符合题意。
句意：太多的人消耗自己的健康来获取财富，然后他们又不得不花费金钱来恢复健康。