“A couple of years”到底是指几年?

“A couple of years”到底是指几年? a couple of years a couple of days.是指几天? 英语翻译that happened a couple of years of years ago.这里的a couple 这个词组“a couple of years”在以下的句子中是何含义? 请问：“a couple of years”和“a couple of year”分别是什么意思?其中有错么? That was the situation until a couple of years late That 代指 可以说a couple of couple? a pair of couple a couple of a couple of hours.. 关于a couple of ..