See report have an effect (4)
I believe the answer is:
tell
This clue might be a double definition.
'see report' is the first definition.
'tell' can be an answer for 'report' (to report is to tell someone about something). I am not sure about the 'see' bit.
'have an effect' is the second definition.
(I've seen this in another clue)
Can you help me to learn more?
(Other definitions for tell that I've seen before include "William .... was legendary Swiss hero-archer" , "toxophilite" , "William ..., skilled Swiss archer" , "Count - give an account" , "his hitting the apple?" .)