Simplify the following text for a Grade 13 native English-speaking person.
Original: Roach has claimed in his book , Coldplay : Nobody Said It Was Easy , that although `` Shiver '' earned the band their debut UK Top 40 single , it was `` Yellow '' that has changed `` everything '' , and that it `` exemplifies so much of what had made Coldplay so popular '' .
Simplified: Roach has claimed in his book , Coldplay : Nobody Said It Was Easy , that although `` Shiver '' earned the band their first UK Top 40 single , it was `` Yellow '' that has changed `` everything '' , and that it `` exemplifies so much of what had made Coldplay so popular '' .