she sat down under a big tree对 (under a big tree )提问

问题描述:

she sat down under a big tree
对 (under a big tree )提问

应该是
Where did she sit down?
特殊疑问句里,对于地点状语提问一半用 Where 开头
将谓语时态还原,其余语序不变就可以了