The secretary was __________ his hands and knees searching for something.

问题描述:

The secretary was __________ his hands and knees searching for something.
A with B down C into D on
为什么选D

D.on
on 在这里表示身体重心靠身体的某个部位支撑,on 接身体部位词
再如:
lie on one's stomach 俯卧
lie on one's back 仰卧
kneel on one knee 单膝跪着请翻译一下此句话,谢谢那位秘书趴在地上(四肢着地)找东西