天龙八部丐帮龙战于野:是hear　sb to do sth 还是hear sb doing sth

是hear　sb to do sth 还是hear sb doing sth 怎样区别hear sb. do sth与hear sb. to do sth的用法？ 是offer sb sth还是 offer sb to do sth? 是advise sb. to do sth.吗？ 是get sb. do sth.还是get sb. to do sth. hear sb do sth 和 hear sb do sth 有什么区别？ help sb. do sth还是help sb to do sth? help sb. do sth还是help sb to do sth? get sb do sth还是get sb to do sth let sb. do sth.or let sb.to do sth