PRONUNCIATION: HIS vs. HE'S
The difference between the sounds i: (he's) and I (his) is the most difficult sound for all students regardless of their native tongue. To read more about the difference between these sounds, to practice pronunciation pairs and to understand the pronunciation element in depth, read The Most Commonly Mispronounced VOWEL Sounds.
GRAMMAR: HIS vs. HE'S
The difference between HIS and HE'S is fairly simple, but students get confused because of the pronunciation. The grammar is straight forward and easy to understand when explained.
HIS is the possessive adjective for HE, of course:
Ex. Don't work on his computer because he's still finishing his reports.
HE'S=HE+IS. It's that simple! He's is a contraction for the verb TO BE:
Ex. He's working on his thesis right now, so please don't disturb him!
I hope this helps....if not, leave a question below. Have a great weekend :)