"Don't worry, I'll change you back" 是一句表达不要担心，我会让你恢复原样的英文表达。这句话中的"change back" 是一个固定搭配，意思是使某物恢复原状。
例句：
"I accidentally deleted the file, but don't worry, I'll change it back." (我不小心删了这个文件，但是不用担心，我会把它恢复原样。)
"I know I made a mistake, but please let me change it back." (我知道我犯了个错误，但请让我把它改回去。)
"Don't worry, I'll change you back to your normal self in no time." (别担心，我会很快让你恢复正常。)