ارجو الافادة من السادة الزملاء

[الاسوانى محمد حسين]

in unit 10 3rd secondary year( sentence with wish) the writer used could with other pronouns apart from (I-WE) also he used could have +pp with wish in the past.
I know that when we use wish + subject we use past perfect in the past. and could with I-WE and would with other prounouns.
please anyone would be knid enough and explain.
another thing please write any "source or " web site to help me.
thank you for your time.