English and French are indeed lingua francas but depending on the country or even the city you're in, they can be used as equally as lingua franca with the dominant local language.
People in Africa fluidly switch languages mid-conversation or even mid-sentence. In DRC for example, it's common to see a conversation in French and Swahili, or French and Lingala, or Lingala and Swahili. But most people will make an effort to stick to French when talking to a foreigner.
I've also heard Kenyans say that Congolese people speak Swahili weird because they use French loanwords.
People in Africa fluidly switch languages mid-conversation or even mid-sentence. In DRC for example, it's common to see a conversation in French and Swahili, or French and Lingala, or Lingala and Swahili. But most people will make an effort to stick to French when talking to a foreigner.
I've also heard Kenyans say that Congolese people speak Swahili weird because they use French loanwords.