to 后面可接句子吗？

xixiokok

0 O, \! B; j0 y  J: f/ e& h, hIn 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
it is necessary to have done sth.
5 R+ s, s2 r% g; Y! O8 [: N接了个完成时的动宾结构

+ |% P# ]5 G5 B- B: F+ h你可以对比一下下面两句的含义
it's necessary to acquire this.
有必要（现在或以后）去获取这个
% m: y! r% q7 x6 |6 V- Kit'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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