Her diligence as a correspondent prevented any but epistolary writing.作为一个勤奋的通信者, 她只写书信, 不写别的。

He acquired several pen pals, and these epistolary acquaintances turned out to be more reliable than his close friends.他找到几个笔友, 结果这些通过信件认识的人却比他的好朋友更值得信赖。

Laclos's famous epistolary novel拉克洛著名的书信体小说

It's written in epistolary form.它是用书信体写成的。