What's the difference between"pair" and "couple"?

Question

Both of them have the same meaning which means "double",but when do we use "pair"and when do we use "couple"?Why don't we say"a couple of shoes"or "a couple earrings"?

Answer 1

paie和couple都可以表示一双一对，但是它们也是有区别的，couple可以指任意两件同类的东西，而pair指两件不能分开使用的东西，它们可以相连也可以指构成一件东西的两个部分。