For a long time I believed that "proper" writing was in English. That was the language of school essays, of the books in the library, of everything that got marked and graded. Kiswahili was for home. Sheng was for the street and for friends. Neither was supposed to appear on the page.

So I wrote stiff, careful English, and it never sounded like me.

Each language holds something different

Kiswahili is the language of my grandmother, of greetings that take five minutes, of proverbs that say in one line what English needs a paragraph to explain. Haba na haba hujaza kibaba — little by little fills the measure. There's no English sentence that feels quite as warm.

Sheng is fast, playful and always changing. It's the sound of matatus and of my cousins teasing each other. It has a rhythm English simply can't copy.

English is where I think in long, organised sentences. It's my working language, and I love it too.

Letting them meet

The change came when I wrote a short story about my aunt and let her speak the way she actually speaks — a sentence that starts in English, swerves into Kiswahili and ends with a Sheng word I had to explain to my editor. It was the first thing I had written that sounded alive.

I don't translate my characters any more. I let them talk.

Who is it for?

People sometimes ask whether readers outside Kenya will understand. Some won't catch every word, and that's all right. I have read hundreds of books full of words I didn't know — French in English novels, Yiddish in American ones — and I never felt locked out. I felt invited in.

If you write in more than one language, I hope you let them all onto the page. They are all yours.