Why are you in such a happy mood?

你为什么心情这么愉快?

It kills your 'buzz', in other words, your happy mood.

它会让你失去兴致，也就是你的好心情。

For example, compared to people in a neutral mood, people in a happy mood tend to make more creative word associations and categorize items in a more open-minded way.

例如，与中性情绪的人相比，心情愉快的人倾向于做出更有创造性的词语联想，并以更开放的方式对物品进行分类。

Even the street organs put me in a happy mood; I owe many a page to them — written when I should else have been sunk in bilious gloom.

甚至街头风琴也让我心情愉快；我欠他们很多篇幅——写在我本该陷入阴郁的时候。

Besides, formerly the occupation with the affairs of Dmitri Ivanovich always caused vexation and irritation; while these affairs of others for the most part put him in a happy mood.

此外，从前忙于德米特里·伊万诺维奇的事务总是令人烦恼和恼火；而这些别人的事，多半让他心情愉快。