Katrina Irso is the only known person fluent in Ngu.

It's one of a group of indigenous South African languages all but stamped out by decades of colonialism and apartheid.

But at 90 years old, Irso doesn't relish being its sole protector.

Ngu was spoken by one of many hunter-gatherer groups that populated southern Africa before the arrival of European colonisers.

These indigenous people spoke dozens of languages in the San family, many of which have gone extinct.

As a child, Irso says, people mocked Ngu as an ugly language.

Instead, she spoke Afrikaans, the language promoted by South Africa's white minority rulers.

Later in life, she realised the importance of preserving her mother tongue.

She started teaching Ngu to local children and opened a school with her granddaughter and language activist Claudia Snyman.

But the school property was vandalised during the global health crisis and now lies abandoned.

Snyman says her grandmother's health has been poor recently and she fears that if Irso dies, her work to protect the language will have been in vain.

Irso has two living sisters, but they do not speak Ngu.

She does not know anyone else who does, save for the family members and children to whom she's taught a few words and phrases.

At a recent ceremony at the University of Cape Town, she was awarded an honorary doctorate for the work she is doing to preserve the language and culture.

I love my language, I love Ngu very much, that's why I don't want to die, I want to continue to live Ngu.

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