请帮忙翻译一下几句话，很容易的

“听了这个故事他们一定会开怀大笑的”用英语怎么说
还有“上课”、“下课”怎么说
“下节课我将要教你们一首非常好听的英文歌，在这节课快要结束时我先唱给你们听一下，让你们大概有个印象，下节课再具体的学习这首歌”

1.It is certainly that they will have a good laugh when hear this story.
2.Let's begin our class.开始上课。Class is over!下课！
3.I will teach you a very beautiful English song next time. Let me sing it when this class coming to the end，then you will have an impression .Next class we will learn this song in detail.

they will laugh out if they liston to this story
上课class begins 下课class over
I will teach you a very orphean English song next class 。I will sing it when this class comes to the end，so you can have an impression 。Next class we will learn this song frondosely

1.After hearing the story,they will surely laugh.
2.attend class
finish class
3.I will teach you a very beautiful English song next class,first at the end of this class I'll sing a piece for you to give you an ordinary impression and you will learn the song in detail next class.

听了这个故事他们一定会开怀大笑的.
After listening to the stories they will be the laughing.