曾經有學生問我一條很好的問題，在此同大家分享：

到底說 no student 還是 no students 才是正確？

其實，兩者都正確，但傾向說成複數形式。

眾所周知，英語名詞有分可數不可數，不可數名詞 (uncountable noun) 沒有複數可言，所以沒有「限定詞 (determiner) "no" 後跟單數還是複數名詞？」這個問題：

I have no time to spare.

No water was wasted in this activity.

但是，可數名詞 (countable noun) 一般來說則會用複數形式，以表達一種 "普遍" (general) 或 "不特定" (non-specific) 的意思。

I can see no dictionaries.
我看不到 "字典" 這東西。

There are no apples on the table.
枱上沒有 "蘋果" 這種生果。

相反，當我們想消除這種 "普遍性"，就要用單數形式。看看以下對話：

A: Where is the dictionary?

B: It's on the table.

A: But I can see no dictionary.

假設枱上向來只有一本字典，那就不能說 "no dictionaries"，否則別人會以為枱上原來有超過一本字典呢。

有些情況基乎是不用複數的，因為不合邏輯。這時候一概用單數形式：

She has no husband. [筆者按：丈夫應該只有一個吧！]

This creature has no head.

You really have no heart!

但假如是 "她沒有小孩" 的話，就要視乎你是否特定地說 "某一位小孩"：

A: Mary didn't bring her child here today.

B: Mary's child? She has no child. That was her nephew.

A: But isn't she married?

B: Yes, she's just married but she has no children so far.

回顧問題，假如你進入一間從未進入過的課室，發覺空無一人，你可以說：

There are no students.

但如果你一向都認為課室內有一個學生，進去才驚覺學生不見了，你就可以說：

How come there is no student here?