I've been working on my own answers to questions like this and found that thoroughly applying the STAR method can help strengthen an answer and give the necessary details that can be easily missed. Here are a few tips:
Situation - maybe add more detail to the moot itself: Was it university-wide? solely for the first years?
Task: specify what tasks you did to complete the moot: drafting, researching, reading, hours of study etc
Action: You could be more specific - what feedback did you receive, and how was the feedback beneficial in identifying/mitigating weakness in your performance/work? Did you take it onboard?
Result: Finally, you could specify the number of moots you won that year and end with a reflection - what did this situation teach you? (The importance of feedback? How to persevere? etc).
Hope this helps