We have only enough food and air for approximately three weeks.
请问这句话for approximately three weeks和enough有关系吗？for approximately three weeks是该剖析为enough的状语，还是该剖析为food and air的定语?
有关系。从意思和结构看， for approximately three weeks 是针对 enough 的，故为状语。大家做个比较：
This question is too difficult for a child.
This is too difficult a question for a child.
We have only enough food and air for approximately three weeks. =
We have food and air only enough for approximately three weeks.
