This is the story of our modern world in 10 languages.

As Sophia Smith Galer's Nonna lay dying, she realised it wasn't just a beloved grandmother she was losing - it was the language she spoke, too. From Northern Italy, she spoke a dialët that Sophia, like so many children and grandchildren of migrants, can understand but can't speak. With the death of the language, Sophia would lose a culture, a history, an inheritance - a whole world.

This tragedy reaches far beyond her family. Globally we are witnessing an unprecedented mass extinction event. By the end of this century half of the world's 7000 languages will be gone, killed by war, climate breakdown, migration, nationalism or neglect, along with the vital knowledge that they have sustained for centuries.

Smith Galer has journeyed across continents and generations to report from this disappearing world. From Ghana to Greece, Ecuador to Oman, California to the UK, she meets people experiencing this loss at first hand - but also campaigners and linguists who prove that a multilingual future is still possible. Her travels ultimately lead her back to where she began: to Italy, and the tiny mountainside village where the church bells still ring out for her Nonna.

How to Kill a Language is the story of our modern world in 10 languages. It is a vital investigation into a hidden global crisis, and a call to speak, read and write the languages of our world, before it's too late.