Simplify the following text for a Grade 14 native English-speaking person.
Original: From 1992 to 2002 he was associate conductor\/composer with the BBC Philharmonic Orchestra and he has conducted a number of other prominent orchestras , including the Philharmonia , the Cleveland Orchestra , the Boston Symphony Orchestra and the Leipzig Gewandhaus Orchestra .
Simplified: From 1992 to 2002 he was associate conductor\/composer with the BBC Philharmonic Orchestra and he has conducted a number of other well-known orchestras .