This is a really confusing word. It is a word used in the same way as “who” but there are subtle and important differences.
One easy tip to know if you should use Who or Whom is to answer the question yourself and see if the answer is “him” or “he”. “Who/Whom are you going to the cinema with?” – “I am going with him” – Him means you should use “whom”
you should use whom with “him” or “her”.
(and also after a preposition: To whom do you wish to speak? )
Whom did you visit at the hospital?
Whom did she invite?
For whom are you making these cupcakes?
in the question. “Who/Whom said the film was really good?” “He did”
The answer is He then use “who”.
you should use who with “he” or “she”.
Who would like to go on vacation?
Who made this decision?
Who wants dinner?