watch用作名词，意思是“手表”时是一个可数名词，这时watch的复数形式是watches。可数名词变复数规则以ch结尾的可数名词，一般在后面加es。
以s,x,sh,ch结尾的名词,及以o结尾的有生命名词,复数形式都是加es。所以watch复数加es,即watches；如果作为动词“观看”,三单形式也是加es,即watches.
watch的复数简单句举例
ls this her watch?（变为复数）
are these her watches?
That is her watch.（变为复数）
Those are her watches.
