Dear Bob:
Thanks(加上for) writing and introducing your beautiful city to me.Now I'd like to tell you anything (anything改为something)about my hometown PingChang,which stand(stand改为stands) on the bank of the Bahe River.
It is a beautiful city for people to live(加上in).Its economy has been developing rapidly in the past 10 years.Now factories,houses and roads have (加上been)built.More schools and hospitals are serving(serving改为in serve或are serving改为serves)