Milton wrote his epic in lines of unrhymed iambic pentameter or what we call, and what Milton would have called, blank verse.

弥尔顿的史诗由不押韵的抑扬格五音步诗句写成,我们，还有弥尔顿都称其为无韵诗。

耶鲁公开课 - 弥尔顿课程节选

Up to this point in literary history, only verse written for the theater had been written in unrhymed lines of iambic pentameter, in blank verse.

文学发展到那时候，只有为戏剧写的诗,才会用不押韵的抑扬格五音步，即无韵诗。

耶鲁公开课 - 弥尔顿课程节选