to 后面可接句子吗？

xixiokok

In order to design policies that aim to change commuting practices it is, however,necessary to have acquired a good understanding of the trips in question and their determinants.  
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& D) M3 t5 I- |5 C; u* z这句话里，necessary to 后面为什么可以接 have acquired a ...句子？

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江南一屁

没有接句子
it is necessary to have done sth.
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你可以对比一下下面两句的含义
0 B: p1 b* z, @it's necessary to acquire this.
* A& z# n- [5 K8 g/ r4 e有必要（现在或以后）去获取这个
it's necessary to have acquired this.
有必要目前已经获取了这个（具有这个是有必要的）
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