his.

he. she， her都可属于人称代词，he(他)，she(她)人称代词主格，句中作主语。her(她)人称代词宾格，句中作宾语。例如:

He is from Australia， She is from Italy.

Mr. Li taught her English 2 years ago.

his(他的)，形容词性物主代词/名词性物主代词，例如:

That is his first job.