- He = who - Him = whom Who / Whom cares for the children? = He cares for the children. Therefore, 'who' is correct. = 'Who' is an interrogative pronoun and is used in place of the subject of a question. It can also be used in statements, in place of the subject of a clause. 'John is the man who got the job.' (He got the job) For who / whom should I write? I should write for him. Therefore 'whom' is correct. = 'Whom' is an interrogative pronoun, but it is used in place of the object of a question. 'With whom are you going?' It can be used in statements, in place of the object of a clause. 'This is the man whom I told you about.'

For answering questions in an exam, follow Learner's advice. For daily use/speaking, we just use "who". We only say "whom" to sound pedantic. ;)