现在完成时的结构：助动词have / has+动词的过去分词.
I've already had = I have already had
为什么不能用was？already 已经，常与现在完成时连用‘我已经吃过午餐了’ ，现在完成时的结构：助动词have / has+动词的过去分词。I‘ ve already had lunch=I have already had lunch