he

We don’t traditionally think of he as having synonyms, but there are some situations in which it can be reworded or replaced with another word or phrase.

he himself

Sometimes, the phrase he himself is used to emphasize that a person did something entirely by himself or that it was done by him as opposed to others. For example, saying He cast the deciding vote may be a neutral statement, but saying He himself cast the deciding vote indicates that there was some significance to the fact that it was he who did it.

him

Sometimes a sentence can be reworded to replace the subject he with the equivalent object him. For example, the question “When do you expect he will arrive?” could be reworded as “When do you expect him to arrive?” In this case, it’s a more natural-sounding question, but this kind of rewording can be done for a number of reasons.

Him is also commonly used after linking verbs (like is and was) in sentences like It was him that I saw on the train or It is him in that picture.