以下是两个单词作副词时的解释。来自新牛津汉英双解大字典，搞不清楚可以查英英解释的字典。
Freely：not under the control of another; as one wishes 自由地；随心所欲地
I roamed freely. 我随意闲逛。
Free：without cost or payment 免费地
Ladies were admitted free. 女士免费入场。
Free 作副词时没有自由的意思，而 Freely 没有免费的意思。
She can speak freely in front of Mack, but she can’t eat free in his restaurant.
她可以在迈克面前畅所欲言，但她不能在迈克的餐厅里吃白食。