问大家英语语法大家好,我学语法中,名词的复数,怎样加有点乱,问问大家.(语法书上说得不清不楚)InBrazil,youshouldwipeyourmouthwithyour(napkin)everytimeyoutakeadrink.这句当中的napkin为何

Question

问大家英语语法
大家好,我学语法中,名词的复数,怎样加有点乱,问问大家.(语法书上说得不清不楚)
In Brazil ,you should wipe your mouth with your (napkin) every time you take a drink. 这句当中的 napkin 为何不加 "s" ?
You should always keep your hands,but not your (elbows),on the table? 为何又要加 ”S” ?
大家请说明清楚些,还有问问大家在啥情况下加 S ? 在句中哪你加?请大家帮帮啊,最好也举个 LI ,谢谢大家咯．

Answer 1

napkin的解释：piece of paper used at meals for wiping one's lips and fingers.with your 后面不一定要跟单数.如：Don't stand with your hands in your pockets.所以,名词的单复数一般情况下,根据可数与不可数；...