pen是可数名词还是不可数

There are many books and pens.

这有许多书和钢笔。

There are two pens on the desk.

桌子上有两支钢笔。

Others prefer pens and pads.

其他人更喜欢笔记本和笔。

What color are these pens?

这些钢笔是什么颜色？

Look! It's my new pens.

看！这是我的新钢笔。