Simplify the following text for a Grade 8 native English-speaking person.
Original: The design of the trains was finalized in September 2004 and manufacture of two pre-production trains began in January 2005 , the first scheduled to be completed by mid-2006 .
Simplified: The design of the trains was finalized in September 2004 , and manufacture of two pre-production trains began in January 2005 . The first train was scheduled to be completed by mid-2006 .