深虑

例句：

1. 1. He spent hours deep in thought before making his decision.
   他在做决定之前花了很多时间深思熟虑。
2. 2. She often meditates on the meaning of life.
   她经常沉思生命的意义。
3. 3. The scientist pondered over the results of his experiments for days.
   这位科学家对实验结果进行了几天的深入思考。