A healthy does of sunshine may be the secret to staying young.为什么_英语解答

A healthy does of sunshine may be the secret to staying young.为什么么不是To stay?

人气：362 ℃　时间：2020-09-17 21:35:20

解答

the secret to sth
这是固定用法、to是介词.
像the way to 、the key to都是一样的用法