Step-by-step explanation:
she wishes that she was a good student
Because she " wishes " indicates for the thing which really hasn't happened but is only wished so this type of questions past tense should be used bit there are two past tenses was, were. she is a singular pronoun so we used was
Hope this was helpful to this plus Other similar questions to Mark me brainliest plz I think my answer is deserving of that （⌒▽⌒）