on weekends是什么时态

on weekends是什么时态 Lingling often goes swimming on weekends 为什么swim要加ing?这句话是什么时态? on the weekends是什么时态跟on the weekend一样都是用将来时吗?on weekend,on weekends,on the weekend on the weekends这四个在句中出现各用什么时态,麻烦能写几个例句让我更明白点吗? 区别at the weekends,on the weekend,at weekends,on weekendsat the weekends,on the weekend,at weekends,on weekends都有些什么区别?各自的意思是什么? 问句子中出现 on weekends , on weekend , on Sunday 分别用什么时态 on weekends on weekends. She often watches TV on weekends.问答句是什么啊? The students of Class Six often help old people do the housework at weekends是什么时态 on weekends是什么意思 on the weekends 翻译 on weekends的同义词 at weekends和on weekends的区别 on weekends 中 weekends 是指几天? 是in weekends 还是on weekends? what's happening on ^可能是什么时态 on weekends、at the weekends、at weekends、on the weekends有什么区别 on weekends=at the weekends吗?或是on weekends=at the weekend还是on weekends=at weekends