on后多接动词的-ing形式,即:on doing sth..意为“一……就……”。
故答案为:arriving 。
希望能够帮到你。请采纳。
on (arriving) 一到......就
1.On arriving home, I was met by my daughter.
到家时我的女儿出来迎接我.
2.On arriving at the shore, the girl struggled up the cliff towards the light she had seen.
一到海岸, 那个女孩就向着她自己所看到的灯光的方向挣扎着往峭壁上爬去.