start from scratch

基本解释

If we have to start from scratch then it all takes time.
如果我們要從頭開始，那麽這一切需要時間。
Start from scratch: Start with an empty set of conditions and add your own.
從頭開始：從一組空的條件開始竝添加您自己的條件。
First of all, if you slip up and damage your reputation at one, you’ll have to start from scratch somewhere else.
首先，如果你犯了錯竝且馬上損害到你的名聲，你就不得不在別的什麽地方從頭開始。

He says the prime minister should declare Japan will not goby the 2006 agreement and will start negotiations from scratch.
and we had to start from scratch together. We did all of our research in the library together.
我們必須從零開始。我們一起在圖書館做研究。
在模擬讅判課堂 - SpeakingMax英語口語達人
You're not going to start for the rest of your life if you ever need to solve a problem with a computer from scratch, odds are you're going to reach for some off the shelf packages or libraries or tools that other people wrote so that people like us don't have to reinvent the wheel again and again.
如果你想用Scratch來解決問題,卻使用其他人寫的程序,或者利用現成的資料或工具,這樣以來,我們的確可以避免做重複性的工作,但卻永遠學不會編程。
哈彿公開課 - 計算機科學課程節選

The best places are refugee economies, where people have had to start from scratch.
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