4. Lionel Shriver

*** 4 Extra broadcast to mark the 25th anniversary

Five internationally acclaimed writers consider the impact of the momentous events of September 11th, 2001.

Ten years on, these authors use imaginative letters to reflect on the consequences for Britain, America and the world.

This letter is by the American novelist Lionel Shriver whose book 'We Need to Talk about Kevin' is now a modern classic.

Shriver has given her letter the title 'Prepositions' and it delineates precisely the meanings of little words such as 'in', 'on', 'at' and 'near'.

Her letter is to a woman whose husband died in 9/11, from a woman whose husband died on 9/11.

Ten years on the consequences of those little differences on the lives of these friends are huge, and vastly different.

Producer: Beaty Rubens

First broadcast on BBC Radio 4 in September 2011.