i saw him dancing和i saw him to dance 意思有不同吗?句子语法有错吗?

和see相关的词组如下：1.see sb do sth 看见某人做某事2.see sb doing sth 看见某人正在做某事【亮点来喽】i saw him dancing 正确：我看见他正在跳舞i saw him to dance 错误：应改为 i saw him dance 我看见他跳舞...i saw him to dance不定式to dance我理解为当him的补语，请问哪里理解错了呢？不是的，这是see的固定用法哦，这里是省略to的不定式如果变成被动语态的话，要还原如： I saw him dance被动就是He was seen to dance by me