I did Judo for two months. To get me up to speed, they kept pairing me up with black belts. Including the instructor, we had 5 black belts. Two of them were interesting characters. The one guy was from Eastern Europe and went WAY to hard at everything. They would have me randori with the black belts every so often. Not going all out to see if I could hold my own against them, but just enough so that I could get the feel of moving around with people who had the techniques down. This European guy would annihilate me when we'd randori. I barely knew how to break falls and he would come in and beat me like I owed him money. When the sensei paired me up with him to learn some ne-waza, I knew things were going to get ugly. I didn't know much aside from a few submission holds I'd seen in books and that wasn't going to do me much good. We'd kneel down, bow, and before I knew it, I was upside down, backwards and being strangled by my gi. Sometimes my hands would be tied up and I'd have problems tapping. I had to struggle to get my leg somewhere near the ground so I could tap out with my foot. I actually learned the most from training with this guy, even though he treated every sparring session as an assassination attempt against me.
The other guy was an older gentleman. He was a nice old man. He tried to help me as much as possible. What was the problem you ask? This guy REEKED of old, stale cigarettes. It was enough to gag a maggot. If there's one thing I learned about myself through these classes, it was that I could hold my breath for much longer than I ever thought possible. He had a gi that was stained beyond recognition too. I always prayed that they wouldn't pair me up with him. They always did. Sometimes he would show my some ne waza and I wanted to tap just from his odor. When he'd put me in holds, I wanted to vomit.
The rest of the class consisted of 12-14 year olds and one 16 year old. I'm 20. I REALLY didn't feel comfortable having to randori with a 12 year old girl. I was always afraid I would fall on her and crush her. The other kids acted like kids with the exception of the 16 year old. I liked working with him. He had been training for quite some time. He was a brown belt. He knew when to do what when we would randori. He didn't kill me, but he went hard enough that I had no choice but to improve a bit. Every so often, he'd allow me to get a throw off on him. I learned a lot from him.
There was a younger kid in that class (a 12 year old boy) who had the worst attention deficit in the world. I have a dissociative disorder and this kid still outclassed me. We'd be training in ne-waza and he'd just start rambling and trying to drive on me. If I said that wasn't a bit unnerving, I'd be lying.
There was a 13 year old girl there that was almost as tall as I am (5'9") and outweighed my by a decent sum. She never spoke and she didn't even attempt to fight back when she'd randori. She was like a log. She'd just let you pull of whatever throw you wanted. However, she was deathly afraid of throws which caused her to flip over, such as Ippon seoinage. If you attempted that on her, she'd freak out and counter it by planting you on the ground. I never thought a 13 year old could manhandle me the way that this girl did when I attempted a seionage on her.