写舍友作文 英语怎么说

"Writing about roommates" 英文翻译是 "writing a composition about roommates"。
"Composition" 在这里指的是文章或者作文，是指一篇写出来的文章或者作文，它可能是一篇记叙文、一篇说明文、一篇议论文或者一篇应用文。
例句：
The assignment was to write a composition about our childhood memories.
(这个任务是写一篇关于我们童年记忆的作文)
He got a good grade on his composition about the effects of pollution on the environment.
(他在关于污染对环境影响的作文上得了一个好成绩)
She wrote a composition about the importance of education for young children.
(她写了一篇关于对幼儿教育的重要性的作文)