开心的英语是：happy。
英 [ˈhæpɪ] 美 [ˈhæpi] 。
解释：
adj. 高兴的；使人高兴的；情愿的；放心的；幸运的；恰当的
词型变化：
名词：happiness 、副词：happily、形容词比较级：happier、 最高级：happiest。
开心的英语例句
在去夏威夷的旅途中，我们都很开心。
On the trip to Hawaii, we were all in high spirits.
玩得开心点。
Have fun.
你在今晚的晚会上一定会玩得很开心。
You'll sure to have fun at the party tonight.
我开心地咯咯笑，告诉他没有什么能比这件事更让我开心了。
I giggled happily and said nothing would make me happier.
用一颗开心的的心，去面对所有不开心的事!
Please face unhappy things with your happy heart!
新的一年我要很开心、开心。
开心的双语例句
1. I might buy one for a friend's birthday as a giggle.
我可能会买一件送给朋友当生日礼物，逗他开心。
2. He was so happy communing with the dolphin in Dingle Bay.
他在丁格尔湾与海豚交流的时候特别开心。
3. Her grandmother had the gift of making people happy.
她奶奶有逗人开心的本事。
4. She had few friends, and was generally not very happy.
她几乎没什么朋友，总的来说不怎么开心。
5. He was having a grand time meeting new sorts of people.
结识形形色色的人让他很开心。