更正楼上答案如下: 改成:It is a long time since we said good-bye to each other. 这是一个固定句式:It is + 一段时间 + since从句,意思是“自从,以来多久了”. 还可以说成:It has been + 一段时间 + since从句. 如果要说成it was a long time也可以,但是其后的since从句时态必须改成过去完成时,即:since we had said good-bye to each other. 如果对你有所帮助,请点击我回答下面的“选为满意回答”按钮,