watch/see/hear sb do sth观看/看见/听见某人做过某事watch/see/hear sb doing sth观看/看见/听见某人正在做某事eg. He can watch actors say the words. Can you hear him singing in the room?see to 负责准备eg. Whose turn to see to the dinner today？ / 今天轮到谁做饭了？
see sb.do sth.表示由开始看到结尾，整个过程。see sb.doing sth.表示看到某人正在做某事，不考虑开始或结尾。see sth./sb.done 表示某件事情被看到。eg.I saw him cross the road.I saw a plane flying to the south.I saw the man killed.
