Revise the underlined part of the following sentence.People should try to bring about a change in the state of affairs when in depression. （请用一个英语单词填空，全部小写。）

Revise the underlined part of the following sentence.People should try to bring about a change in the state of affairs when in depression. （请用一个英语单词填空，全部小写。）
正确答案：change