email是可數名詞還是不可數名詞

I haven't answered her email yet.

我還沒有回覆她的電郵。

The Net's real killer app is email.

因特網真正的殺手應用軟件是郵件。

They sent a global email to all staff.

他們向全體職員發了一封統一的電郵。

They each have their own email address.

他們每個人都有自己的電子郵件地址。

You can send faxes by email from your computer.

你可以透過計算機用電子郵件發送傳真信件。