I am almost at the finishing line with my novel and I am just polishing off a few details, and this is one of the details which I have left until last. There are some scenes in my novel where there are groups (big and small) of young adults. Now, if they were adults I wouldn't have a hard time using man and woman, and girl and boy for children and teenagers, but for young adults.... I'm stuck. I find calling an 18-20 year old in my novel a woman as it makes them seem much older than they actually are- some don't behave like an adult anyway. My husband said that, to him, calling them girls rather than women sounded better, but then I had the issue of calling the young men boys, which, to me, makes them sound far younger than they really are. So, going from man/woman to boy/girl I then decided to try young man/young woman, but the extra words took the flow away, it got repetitive. I even thought about girl/guy but 'guy' sounded too informal. What are your suggestions?