Simplify the following text for a Grade 11 native English-speaking person.
Original: The Guardian 's Kate Kellaway said `` An immense achievement , Half of a Yellow Sun has a ramshackle freedom and exuberant ambition , '' after reading the book .
Simplified: The Guardian 's Kate Kellaway said `` An immense achievement , Half of a Yellow Sun has a ramshackle freedom and exuberant ambition . ''