For Chinese control sentence, "Zhangsan de fuqin ganxie Lisi bangzhu LE ta"'
"Zhangsan 's father thank Lisi help PERFECT ASPECT he "
Zhangsan's father thanks Lisi for helping him.
I have learned in English there is a PRO between the "for" and "helping", in terms of phrase structure grammar.
Zhangsan's father thanks Lisi[PRO for helping him].
The small clause "PRO for helping him" is a nonfinite clause so PRO doesn't need to be assigned Case. For Chinese sentence, there is a aspect marker "LE" to indicate that "Lisi" has helped him. So I am assuming we can't use PRO anymore because it is a finite clause. But in HU Jianhua2006 he assumed the sentence to be "Zhangsan's father thanks Lisi [PRO for helping him]." This kind of sentence is also called "Jianyu ju" in older Chinese modern grammar. In this sense, do we allow to change the rule of "finite clause must assign case to NP necessarily " since in some Chinese sentence there exists this problem? So I am wondering if in this case, the finite clause in Chinese don't need to assign Case for the subject PRO.