1) delist means to remove from a list
2) Minimal pairs for English - Listening Exercises - Listening Comprehension for the Pronunciation differences between the sounds 'ae' as in 'cat' and 'eh' as in 'let'
3) wrongful (adjective only) wrong (noun, verb, adjective or adverb)
right had many meanings see: Definition of right - Merriam-Webster Online Dictionary
but Righteous has just a couple see: Definition of righteous - Merriam-Webster Online Dictionary
4) No change is (one change) No changes are needed (more than one change)
Student or Learner