The boys did wrong, swimming in the river (7)
I believe the answer is:
teddies
'the boys' is the definition.
Although both the answer and definition are plural nouns, I can't understand how they can define each other.
'did wrong swimming in the river' is the wordplay.
I cannot quite understand how this works, but
an anagram of 'did' is 'ddi' which is within the answer.
'river' could be 'tees' (River Tees ) and 'tees' is found in the remaining letters.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for teddies that I've seen before include "Undergarments and children's toys" , "Soft toy bears" , "Children's toy bears" .)