Yesterday's lesson was about describing a festival in your country. I received a good question about this topic:
"When describing a festival, can we use words from another language?"
Maybe there is no English name for some special food you eat, or particular clothes that people wear. In this situation I think it's fine to use a word from your language.
Just describe what the word means so that the examiner understands e.g. We eat a type of food called (word in your language) which contains... This food is special because...