But I can't afford it.

但我负担不起。

Unfortunately, I can't afford it now, but Christmas is coming, so I can ask my parents for a stereo for Christmas, but I'm not sure if they will agree or not.

可惜现在买不起，但是圣诞节快到了，可以找父母要一台音响过圣诞节，但是不确定他们会不会同意。

This pen is too dear, I can't afford it.

这支笔太贵了，我无法承担。

The black fox scarf is very expensive. I can't afford it.

玄狐毛的围巾很贵的，我买不起。

For example, one dad had a habit of saying, I can't afford it.

例如，一位爸爸爱说我可付不起这样的话，

He believed that automatically saying I can't afford it was a sign of mental laziness.

在他看来，轻易就说我负担不起这类话是一种精神上的懒惰。