salad是可數(shù)名詞嗎為什么有時(shí)候+s

　　例句：

　　The salad had lost its crispness.

　　這色拉已經(jīng)不脆了。

　　Can I help you to some more salad?

　　再給你來(lái)點(diǎn)色拉好嗎？

　　I think I'll go for the fruit salad.

　　我想要水果色拉。