I have always been practising cases in English. However, in my recent interviews with MBB, most were conducted in the local language. Although it is my mother tongue, I was actually much more confident and comfortable to discuss the case in English. Discussing the case in local language makes me lose the sense of driving the case and thinking about the case information.
I'm wondering around what percentage of the case I practice should be practised in the local language to solve this problem?