Hey, thanks for your answer!
Haha you are right with npexp
Now I have two more questions because I'm a little confused with the non-finite clauses:
A very good student always doing his homework, he will pass the exam.
--> Is "a very good student always doing his homework" a non-finite clause too or is this a noun phrase?
and the same question for: The only student to do his homework, he will pass the exam.
You have to do your homework before going to bed.
--> Is "before going to bed" a non-finite temporal adverbial clause or is "going to bed" a NP?
Thanks so much!