to 后面可接句子吗？

xixiokok

) w5 L* h/ S4 ^2 ^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.  

9 }7 n; a# m" j- `8 R' Y" ~/ }; I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
6 {. I$ x% e6 |% J2 U5 ?it is necessary to have done sth.
* t9 U1 {" R! u$ u; a" 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
it's necessary to acquire this.
* f7 i) p5 M0 K0 {9 W% J8 v9 _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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