n. 同窗, 同学

playmate/schoolmate/classmate/roommate/desk/mate
记忆：
1. playmate [5pleImeIt] n. 玩伴, 游伴 The playmates in our childhood now working all over China. 我们童年时候的玩伴如今在全国各地工作。
2. schoolmate [5sku:lmeIt] n. 同窗, 同学 He has such a good memory that he knows every one of his schoolmates’ name. 他记性很好，他知道每一个校友的名字。
3. classmate [5klB:smeIt] n. 同学 She gets on well with every classmate. 她与每个同学都相处得很好。
4. roommate n. 室友 As roommates, we ought to help each other. 作为室友，我们应该互相帮助。
5. desk mate n. 同桌 You may ask your desk mate to be the practicing partner. 你可以请你的同桌作为练习的搭档。
另类阅读：
Liping was my playmate in the childhood. We were deskmates as well as roommates and classmates in our junior middle school. Now we are schoolmates in the senior school.