"已经答应了" 的英文表达是 "have already agreed"。
这个表达来源于英语动词 "agree"，意思是 "同意"。
例句：
I have already agreed to meet him at the coffee shop at 3 o'clock. (我已经同意在 3 点在咖啡店见他。)
She has already agreed to help us with the project. (她已经同意帮助我们完成这个项目。)
They have already agreed to come to the party. (他们已经同意参加聚会。)