... did seem to be a bad thing to do (7)
I believe the answer is:
misdeed
'a bad thing to do' is the definition.
I can't tell whether this defines the answer.
'did seem to be' is the wordplay.
'to be' indicates an anagram.
'did'+'seem'='didseem'
'didseem' anagrammed gives 'MISDEED'.
Can you help me to learn more?
(Other definitions for misdeed that I've seen before include "Improper, wicked or immoral behaviour" , "Illegal/wicked act" , "Improper act" , "Wicked/illegal act" , "Wicked or illegal act" .)