sb was doing sth when sth 再造个句子 3Q

sb was doing sth sb was doing sth when sth +动词过去式是什么时态 when sb doing sth,sb doing sth 这个句型可不可以? when sb.do sth.还是 when sb.doing sth. 什么时候when sb do sth 可变成when doing sth 问个with sb.doing sth结构的句子 用 1 stand doing sth 2 love doing sth 3 like doing sth 造个句子 when while and see sb doing sth see sb.doing sth. sb in doing sth help sb doing sth have sb doing sth