是in the weekend还是at the weekends

是in the weekend还是at the weekends 是“at the weekends"还是“at weekends"? on weekends=at the weekends吗?或是on weekends=at the weekend还是o at weekends和at the weekend 区别 我们说 on weekend ,at weekend,还是in the weekend 是at the weekend 还是用in?还是其他的~ at the weekends,at weekends,at the weekend,at weekend 怎么区别? at the weekends和at the weekend和at weekend和at weekends有什么区别 是on the weekends还是at she weekends 英语中,是in weekends 还是in the weekends ,急! 区别at the weekends,on the weekend,at weekends,on weekends 我要北 at the weekend 和at weekends有什么区别?