I'm a little sense of achievement when I see I have already written so much.see能用原型么？

能 have a sense

I have a little sense of achievement when I see I have already written so much.

就应该用原形see
当我看到我已经写了那么多时，我就有了成就感。

你写的这句貌似有些问题。

我改了一下：
I have a little sense of achievement when I see I have written so much.

应该是I have a sense of...的搭配。

had written是过去完成时态，而你现在还没写完，还正在写。
所以应该是现在完成时的have written,表示到现在为止写了多少,还在继续写。

希望对你有帮助。