The dictionary listing for [versieben](http://dictionary.reverso.net/german-english/versieben) has:

> 
> **versieben** ver•sie•ben ( **versiebt** ptp) vt 
> 
> 
> inf (=vergessen) to forget 
> 
> 
> (=verlieren) to lose 
> 
> 
> (=verpfuschen) to make a mess of *inf* 
> 
> 
> 

There are two *inf*'s in here. What do they mean? I've tried to find an answer in the dictionary website as well as using Google, but couldn't find one.