作为作业，我希望你写一篇关于濒危物种的论文。

For homework, I want you to write an ___essay on endangered species.

我可以多写一篇论文来练习我的写作技巧。

I could write an extra ___essay to practice my writing skills.

学生经常提交一篇论文作为期末考试的一部分。

Students often submit an ___essay as part of their final exam.