Simplify the following text for a Grade 8 native English-speaking person.
Original: Alexander Graham Bell ( March 3 , 1847 â `` August 2 , 1922 ) was an eminent scientist , inventor , engineer and innovator who is credited with inventing the first practical telephone .
Simplified: Alexander Graham Bell ( March 3 , 1847 - August 2 , 1922 ) was a teacher , scientist , and inventor .