gravely

No, I should never love anybody better than papa,' she returned gravely.

“不，我永远不会爱任何人胜过爱爸爸，”她严肃地回嘴。

"Yes, well – that certainly happened to me, " he said gravely, recounting the first time he learnt a Latin name of a plant.

“呃，是的——那个我也经历过，”他严肃地说，回顾他头一次知道某种植物的拉丁名的感觉。