孩子们很喜欢划船。他们划得很好。-----Children like boating, and they are good at it. "我坐在划上高兴机了" should be "我坐在船上高兴极了" 我坐在船上高兴极了，也像孩子一样玩儿。-----Sitting on the boat, I was very happy and playing like a kid. 张先生休息得很不错。-----Mr. Zhang had a good rest. 这辆汽车开得很快。-----This car runs very fast. 他汉语说得真好。-----He speaks Chinese very well. 你们别客气。谢谢，我们不客气。-----Help yourselves. Thank you. 我最喜欢吃饺子了。-----I like dumplings most. 我过得很愉快。-----I had a good time. Does it help?