Jill crossed her legs and rested her chin on one fist, as if lost in deep thought.

吉尔两腿交叉，下巴抵在拳头上，似乎陷入了沉思。

《柯林斯英汉双解大词典》

The whole night the Tree stood still and in deep thought.

整个晚上，枞树静静地站着，陷入了沉思。

youdao

The Rat looked very grave, and stood in deep thought for a minute or two.

水鼠兰特看上去很严肃，站着沉思了一两分钟。

youdao

Barnes raised the field glasses up, lowered them, pursed his lips as if in deep thought, and then said, in a newly formed sarcastic voice, Hell, you missed the whole thing, Lee.

NEWYORKER: The Tree Line, Kansas, 1934

After he left, our room seemed to be swirling with fresh air, and Father was deep in thought the entire day, looking intently at the newspaper.

NPR: Literature and Lullabies from the 'Axis of Evil'

Advanced technologies have made it possible to not just extract more oil from conventional sources previously thought tapped, but frack and deep-water drill in spots not even thought of 20 years ago.

FORBES: America's (Un)Peak Oil