"Hey Paul, I see you've unpacked your new PC. It looks great!"
"Yes, it looks great, but looks can be deceiving!"
"What's the problem? You don't seem very happy about it?"
"Yes, you're right, it needs to be returned."
"Does it not start up at all?"
"No, it was delivered faulty - in fact worse than just faulty: it doesn't work at all - not even a screen light!"
"Oh dear, well I hope you can sort it out!"
Just my luck, the new computer arrived and it won't power up...its a dud! /DOA!
A dud is a great old word ;-)) A thing that fails to work properly or is otherwise unsatisfactory/usless or worthless! But sometimes technology fails immediately!
"Just my luck, the new computer arrived and it won't power up...its a dud! /DOA!"
"Dud"という言葉は古いものになります。物がきちんと動かなかったり、不満足や役に立たない、価値がない製品に対して使います。
ですが、時々初期不良ということもありますよね。
"Just my luck, the new computer arrived and it won't power up...its a dud! /DOA!"（運が悪かったのか、新品のパソコンが到着時から電源がつかない...初期不良だ！）
I think the first time I heard this, people used it to talk about cars. People now use it with any product. I thought it was US slang, but I checked on the Internet and I see it has been used for more than 100 years both in the US and the UK.
Faulty' describes that the item has a fault. A fault is a mistake, glitch or failure which results in the product or project not working properly. It can be used to describe something that doesn't work to begin with, or worked for a while and then stopped working. When returning the item to the store, some store clerks may ask you what the fault is.
"It's faulty!"
"This thing is faulty!"
"I need to return this product, it's faulty"
"What is the fault, sir?" - "It won't switch on" etc.
'Dud' is a slang term for something that is defective, doesn't work and is basically useless.
"It's a dud"
"It's a total dud!"
Faulty'とは商品が"falt"（不良）という事を表現しています。
"fault"とは商品やプロジェクトなどが不良、問題、誤作動など 上手くいかないという様な意味になります。
これは初めから上手くいかないような状況を表現することが出来ます。
または、調子よく言っていたけど途中で止まったりするようなときにも使います。
お店に返品する時など、店員さんは何が問題なのか尋ねてくるかもしれません。
【例】
"It's faulty!"
（これは不良品です）
"This thing is faulty!"
（これは不良品です）
"I need to return this product, it's faulty"
（これを返品します、不良品です）
"What is the fault, sir?"（何が問題ですか？）
"It won't switch on" （電源が入りません）など
'Dud'（役に立たない）とは俗語/スラングで欠陥品でうまく作動しない、基本的には役に立たない、という様な意味になります。
"It's a dud"
（こはだめだ！）
"It's a total dud!"
（これはクズだ）
The new computer I bought is defective. I need to use the warranty to fix it.
A warranty is a written guarantee, issued to the purchaser of an article by its manufacturer, promising to repair or replace it if necessary within a specified period of time.
For example:
"The car comes with a three-year warranty".
A warranty は、工場が購入した人に発行する書面の保証書です。
これは、有効期限内であれば交換、修理を約束するものです。
例
"The car comes with a three-year warranty".
この車は3年の保証付きだ。
“It malfunctioned from the beginning “this explains that the computer started off with a problem and that you were hardly able to use it smoothly.
“It failed to work properly from the start/beginning “ this explains the computers condition from the time you started operating it.
“It malfunctioned from the beginning“
（最初から不具合がありました。）
これはそのコンピュータが最初から問題があり、あなたは円滑にそれを使えなかったことを説明しています。
“It failed to work properly from the start/beginning “
(最初からうまく動かなかった。)
あなたが使い始めた時点での、そのコンピュータの調子を説明しています。
We can that the product had an, "initial failure," but we can also say that the product was, "fault from the beginning." When something is a, "dud," it means that it stopped working immediately after trying to use it.
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