Final answer:
After being freed from prison, Nelson Mandela and President F. W. de Klerk worked together to rewrite the South African constitution.
Step-by-step explanation:
After Nelson Mandela was freed from prison in 1990, he and President F. W. de Klerk worked together on rewriting the South African constitution. De Klerk visited Mandela in prison and initiated reforms such as ending apartheid and lifting the ban on the ANC operating as a political party. This collaboration set the stage for a more inclusive and democratic South Africa.