The following items deal with the past thinking of someone relating to a past action /situation that went unrealised or not attained.  He imagined a non-fact to be an actual fact.  He thought how good it would have been if something realised or happened favourably.  Part -3 is more or less the same as part 2 except that it relates to a past situation not realised , but reported in the past itself.  Here the reporting verb should be in the past.( i.e  ‘ I wished’ , and NOT ‘I wish’.  That is the only difference.  It can be viewed in three perspectives, viz (a) action based, (b) state based (c) possession based.

STRUCTURE :  Use Past Perfect Tense after ‘ Wished’.

EXAMPLES ( action based).

• I wished I could have sung like him.( i.e in the past I wished something which I was not able to do)
• They wished they could have built a palatial house.(i.e it was their unsuccessful desire and they regretted it in the past)
• I wished I could have run like P.T.USHA.
• She wished she could have passed the exam with a first class.
• I wished I could have helped you.
• I wished I had known his phone number.
• I wished it had not been raining.(i.e I wished so, but it was raining)
• He wished he hadn’t had to work on Sundays.(i.e against what he wished, he had to work on Sundays.)