sandwich是可數(shù)名詞還是不可數(shù)名詞

　　Right, who's for a toasted sandwich then?

　　好了，那誰想要一個吐司三明治呢？

　　She took a couple of bites of the sandwich.

　　她咬了兩口三明治。

　　The sandwich bar is generally packed at lunchtimes.

　　在午餐時間三明治柜臺前通常都擠滿了人。