Look at the last two lines: "But that two-handed engine at the door stands ready to smite once, and smite no more."

看一下最后两行：,“然门边的双手引擎“,整装待发着发出毁灭性的打击“

耶鲁公开课 - 弥尔顿课程节选

Whatever the two-handed engine is, it will smite once and smite no more.

不论双手引擎是什么，它都会不断的进行攻击。

耶鲁公开课 - 弥尔顿课程节选

It stands ready to smite once and smite no more.

它会不止一次的发出攻击。

耶鲁公开课 - 弥尔顿课程节选