Speaking of which, 意思是“说到这”，“谈到这”，可能是对方或你自己提及某事时，突然想到这事，要发表一下观点：

Speaking of which, don’t you think you’ve had more than enough CDs.

谈到这，你不认为你的唱片已经够多了吗?

Speaking of which, I’m afraid I need to tell you something.

谈到这，我正好不得不告诉你一些事。

Speaking of which, let’s give it another try.

谈到这，我们再试试吧。

“我不太想做某事”的表达法：

I don’t feel like doing something，

意思是现在没心情做某事。

My job has kept me rather exhausted, and I don’t feel like going out tonight.

我的工作让我筋疲力尽，今晚不想出去了。

I don’t feel like eating or doing anything since my boyfriend left me for another woman.

自从我男友为了另一个女人离开我之后，我不想吃，不想做任何事。

Sorry, I just don’t feel like doing it.

对不起，我就是不太想做。

I don’t feel like meeting them right now.

我现在不想见他们。

I don’t feel like dancing this moment.

我此刻不想跳舞。

相反，如果有心情做某事，就是“feel like doing something”

I feel like having a cup of coffee.

有点想喝杯咖啡了。