pensiveness

黄昏时分，她坐在窗边，陷入深深的沉思之中。

At dusk, she sat by the window, lost in deep ___pensiveness.

他的沉默不是冷漠，而是一种充满愁绪的沉思。

His silence was not coldness but a kind of melancholy ___pensiveness.

那幅画中人物低垂的目光流露出一种梦幻般的沉思。

The downcast eyes in the painting convey a dreamy ___pensiveness.