1, his is an adjective possessive pronoun, that is, he: it is a kind of possessive pronoun (the other is a nominal possessive pronoun), which is placed in front of nouns to play a decorative role and indicate someone's. The possessive pronouns of adjectives are: my (mine), your (yours, yours), our (ours), his (his), her (hers), its (its) and their.

2.him is the form of he objective case: the objective case is a personal pronoun, and personal pronouns can be divided into nominative cases. The nominative case includes me, him, her, it, you and the accusative case includes me, him, her, it, you, us and them. The nominative case should be placed in the subject position and the accusative case in the object position.

Second, the usage is different:

1, his? Usually it is followed by a noun: it can only be placed in front of the noun as an attribute, for example, this is his pen. Adjective possessive pronouns have the characteristics of adjectives and are often placed before nouns as attributes, indicating that the person or thing represented by nouns is "whose" or "belongs to someone".

He is usually used as an object after a verb. He is in the accusative form and can only be used as an object after a verb, such as I hit him.

Third, the meaning is different:

1, his means "his". Brian splashed water on his face and then brushed his teeth. Brian washed his face with water and then brushed his teeth.

He means "he", but he needs to follow the verb. John's aunt died suddenly, leaving him a large legacy.