A momentous event, change, or decision is very important because it will shape what comes next.

A momentous重大的 event, change, or decision事件、改變或決定 is very important之所以非常重要 because是因為 it will shape what comes next它將影響接下來會發生的事。

Leaving home, a peace deal, a vote that turns a country — those can be momentous.

Leaving home離家, a peace deal一項和平協議, a vote that turns a country一場扭轉一個國家的投票——those這些 can be momentous都可能是重大的。

The word is formal and serious; speeches and history writing love it.

The word is formal and serious這個詞正式又嚴肅; speeches and history writing love it演講和歷史寫作很愛用它。

It is not about how long something lasts. Though actually, the moment inside this word is an older meaning: weight, importance, not a tick of the clock. So a momentous silence is a silence that matters a great deal, not a short one.

It它 is not about所指的不是 how long something lasts某件事持續的時間長短。Though actually不過其實, the moment inside this word這個字裡的moment is是 an older meaning一個較舊的意思：weight, importance重量、重要性, not a tick of the clock而不是時鐘的一聲滴答。So所以, a momentous silence一個momentous的沉默 is是 a silence that matters a great deal非常重要的沉默, not a short one而不是短暫的沉默。

Students often reach for this word when they only mean “a moment,” and it comes out too heavy. Save it for things whose later effect is large.

when they only mean “a moment,”當他們其實只是想表達「一個片刻」的意思時, Students often reach for this word學生常常會用這個字, and結果 it comes out too heavy聽起來太over太沉重了。Save it把它留下來 for things給那些 whose later effect is large後續影響很大的事情。