The focus of post-disaster efforts is the reestablishment of electricity and water supply systems.

reestablishment 是由前缀 re-（表示"重新"）和动词 establish（建立）加上名词后缀 -ment 构成的名词。re- 表示"再次"，establish 意思是"建立、设立"，-ment 是表示行为或结果的名词后缀。reestablishment 合起来表示"重新建立、恢复"的意思。