it后面加什么

　　例句：

　　It really isn't half bad, is it?

　　這的確很不錯，對嗎？

　　I've had it. Let's call it a day.

　　我受夠了。我們今天就到這里吧。

　　Does it matter what colour it is?

　　它是什么顏色重要嗎？