The sudden knocking at the door startled me when I was lost in deep thought.

我正在沉思，突如其来的敲门吓了我一跳。

youdao

Lost in deep thought, I didn't hear the phone.

沉溺在深思中，我没听到电话声。

youdao

Lost in deep thought, I didn't hear the phone.

沉溺在深思中，我没听到电话声。

youdao