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.  

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

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没有接句子
8 _3 M9 X6 z; D( m0 N* fit is necessary to have done sth.
' A6 C. S  v2 o5 v: E$ q接了个完成时的动宾结构
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你可以对比一下下面两句的含义
3 K! m3 z- H, l- E9 @0 G  U! Oit's necessary to acquire this.
有必要（现在或以后）去获取这个
3 Z, J+ i0 O& s% l4 cit'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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