They play on the sands for an hour,and when they returned they found their goods were stolen.问:sand 为什么要加s?It`s bad manners to speak with your mouth full of food.问：这里为什么用manners 而不用manner?

They play on the sands for an hour,and when they returned they found their goods were stolen.问:sand 为什么要加s?It`s bad manners to speak with your mouth full of food.问：这里为什么用manners 而不用manner?
They play on the sands for an hour,and when they returned they found their goods were stolen.
问:sand 为什么要加s?
It`s bad manners to speak with your mouth full of food.
问：这里为什么用manners 而不用manner?

They play on the sands for an hour,and when they returned they found their goods were stolen.问:sand 为什么要加s?It`s bad manners to speak with your mouth full of food.问：这里为什么用manners 而不用manner?
sands 沙滩 sand 沙子
manners 礼貌 manner 方式,样式

sand是沙
sands是沙滩
manner方式,方法,样式
manners礼貌,规矩

表示沙滩通常用复数形式，sands
在解释为礼貌、礼仪、风俗、习惯的时候要用复数manners.

1.sands表示沙滩.
2.如果要用但数,前面应该加个"a".主要是这里是概称,统称,所以要用复数形式.
:>

sand是沙子，加s表示沙滩
manner表示行为；举止， 加s 时是礼貌的意思