once /wʌns/ star5 CET4 TEM4

• 1.  

  ADV（副词） If something happens once, it happens one time only. 一次 [ADV with v]

  例：

  I met Miquela once, briefly.

  我见过蜜凯拉一次，时间很短。

• 2.  

  PRON（代词） Once is also a pronoun. 一次 ['the/this' PRON]

  例：

  "Have they been to visit you yet?"—"Just the once, yeah."

  “他们已经去看过你了吗？”— “来过，就那一次。”

• 3.  

  ADV（副词） You use once with "a" and words like "day," "week," and "month" to indicate that something happens regularly, one time in each day, week, or month. 每隔…一次 [ADV 'a' n]

  例：

  Lung cells die and are replaced about once a week.

  肺细胞约每周死亡、更新一次。

• 4.  

  ADV（副词） If something was once true, it was true at some time in the past, but is no longer true. 从前

  例：

  Her parents once ran a shop.

  她父母从前开过一家商店。

• 5.  

  ADV（副词） If someone once did something, they did it at some time in the past. 曾经 [ADV with v]

  例：

  I once went camping at Lake Michigan with a friend.

  我曾和一个朋友去密执安湖野营。

• 6.  

  CONJ（连词） If something happens once another thing has happened, it happens immediately afterward. 一…就

  例：

  The decision had taken about 10 seconds once he'd read a market research study.

  他读完一份市场调研报告后，10秒钟就做出了决定。

• 7.  

  PHRASE（习语） If something happens all at once, it happens suddenly, often when you are not expecting it to happen. 突然

  例：

  All at once there was someone knocking on the door.

  突然有人敲门。

• 8.  

  PHRASE（习语） If you do something at once, you do it immediately. 立刻

  例：

  I have to go at once.

  我得马上走。

• 9.  

  PHRASE（习语） If a number of different things happen at once or all at once, they all happen at the same time. 同时

  例：

  You can't be doing two things at once.

  你不能同时做两件事。

• 10.  

  PHRASE（习语） For once is used to emphasize that something happens on this particular occasion, that it has never happened before, and may never happen again. 就此一次[强调]

  例：

  For once, Dad is not complaining.

  就这一次，爸爸没有抱怨。

• 11.  

  PHRASE（习语） If something happens once again or once more, it happens again. 再一次

  例：

  Amy picked up the hairbrush and brushed her hair once more.

  艾米拿起梳子，又梳了一遍头发。

• 12.  

  PHRASE（习语） If something happens once and for all, it happens completely or finally. 最终地[强调]

  例：

  We have to resolve this matter once and for all.

  我们必须彻底解决这件事情。

• 13.  

  PHRASE（习语） If something happens once in a while, it happens sometimes, but not very often. 偶尔

  例：

  Your body, like any other machine, needs a full service once in a while.

  你的身体就像其他机器一样，偶尔也需要一次全面保养。

• 14.  

  PHRASE（习语） If you have done something once or twice, you have done it a few times, but not very often. 一两次; 几次

  例：

  I visited once or twice.

  我参观过一两次。