大三的英语是Junior。
例句：
1、那是我大三和大四之间的暑假,我得到了一份暑期工作。
It was the summer between my junior and senior years, and I was offered a summer job.
2、这些帽子分小、中、大三个尺码。
The hats are made in three sizes: small, medium and large.
3、巴纳德学院的一位大三学生伊丽莎白·德雷瑟说，“我更喜欢课后论文，因为这是真正关于写作的，所以你会有时间去编辑和做更多的研究。”
"I prefer take home essays because it is then really about the writing, so you have time to edit and do more research," says Elizabeth Dresser, a junior at Barnard.
4、你能想象一片比印度大三倍的沙海吗?
Can you imagine a sea of sand three times bigger than India?
5、大三学生使用App跑步打卡的成绩达到及格以上标准才可参与体质测试。
Junior students have to finish the required running times before they take the physical fitness test.
