یه پیام از جنگ جهانی دوم که به پای یه کبوتر نامه بر مرده بسته شده به دست اومده اما خیلی سخت میشه فهمید توش چی نوشته شده. در پادکست انگلیسی BBC – کبوتر نامه بر می شنویم که کالم Callum و نیل Neil درباره ی پیام های رمزنگاری شده و کبوترهای نامه رسان صحبت می کنند و در این مسیر کلمات جدید و کاربردی هم به شما یاد میدن.

پادکست انگلیسی BBC پادکست انگلیسی VOA پادکست سطح‌بندی British Council

سوال پادکست انگلیسی BBC – کبوتر نامه بر :

Who was the first person recorded to use written codes to keep his communications secret?

a) Julius Caesar

b) King Harold

c) Tutankhamun

به پادکست خوب گوش کن تا جواب رو پیدا کنی.

اگر می خوای گوش دادن به پادکست تا حد امکان برات ساده و کارآمد باشه مراحل زیر را دنبال کن:

هر روز به پادکست گوش کن. وقتی براش یه وقت ثابت در روز در نظر بگیری برات تبدیل به عادت میشه و این عادت هرروز پیشرفت میکنه.

پادکستی رو پیدا کن که موضوعش برات جالب باشه. وقتی از خود موضوع لذت ببری یادگیری هم برات لذتبخش میشه.

به پادکستی گوش کن که transcript یا متن داره. این بهت کمک می کنه تا کلمات و عبارات جدید رو به سرعت در متن پیدا کنی و ساختار انواع مختلف جمله رو خوب یاد بگیری.

پس از گوش دادن به پادکست با متن، در مرحله بعدی سعی کن بدون نگاه کردن به متن این کار رو انجام بدی. این کار مهارت شنیداری رو تقویت می کنه و کمک می کنه تا انگلیسی زبانان بومی را راحت تر درک کنی، حتی اگر خیلی سریع صحبت کنن.

اگه به پادکست انگلیسی گوش کردی و نتونستی کامل متوجه اش بشی، ناامید نشو. پادکست هایESL -English as Second Language بیشماری وجود دارن که برای سطوح مختلف، از ابتدایی تا پیشرفته طراحی شدن. مطمئنا هر روز می تونین یه پادکست مناسب با سطح خودت پیدا کنی.

فراموش نکن که هرچی بیشتر تمرین کنی در اون مهارت رشد میکنی! به قول انگلیسی ها: Practice makes perfect


واژگان کلیدی پادکست انگلیسی BBC - کبوتر نامه بر

معنی به فارسیمعنی به انگلیسیواژه
کبوتر، کفتر a common birdpigeon 
دودکش a brick structure in a house which takes smoke from a fireplacechimney 
رمزگشایی کردنto work out the meaning of a hidden messageto crack /break a code
رمز یکبار مصرفa tool or technique for creating unbreakable codesone-time pad 
تصادفی، شانسیunique, unpredictable, without any patternrandom 

BBC 6 minute English - Messenger bird from the past

پادکست انگلیسی BBC - کبوتر نامه بر
برای دانلود پادکست روی سه نقطه سمت راست کلیک و گزینه Download را انتخاب کنید.

پادکست انگلیسی BBC - کبوتر نامه بر

Callum
Hello I’m Callum and this is 6 Minute English. With me today is Neil, hello Neil

Neil
Hi Callum

Callum
In today’s programme we’re going to be looking at an interesting story of war, secret messages, codes and…..

Neil
And, and what

Callum
Pigeons

Neil
Pigeons

Callum
Yes, pigeons

Neil
Those birds that are everywhere in London

Callum
That’s it

Neil
Well, what do they have to do with war, secret messages and codes

Callum
Well, we’ll find out after today’s question. A question about codes. Who is the first person recorded using written codes to keep his or her communications secret? Was it Roman emperor, Julius Caesar, English king, Harold or Egyptian pharaoh, Tutankhamun

Neil
I have no idea whatsoever. So I’m going to go for the English king, Harold. For no reason at all

Callum
OK. We’ll find out if you’re right at the end of the programme. Now, back to the pigeons

Neil
Yes, I am intrigued

Callum
It all started when a man was cleaning out the chimney of his house in the south of England. In the rubbish from the chimney he found a pigeon’s leg. Attached to the leg was a small container and inside the container was a message written in code. From details on the paper it was clear this was a military message from the Second World War

Neil
Were birds really used to carry messages during the Second World War

Callum
Well here’s BBC security correspondent Gordon Corera answering that question and also explaining why. What reason does he give

Gordon Corera

There were important messages carried by pigeon. Particularly, the theory is, that this might have been an army unit, in Europe, on the move, and it was on the move and basically it was moving so fast it couldn’t put up an aerial for a wireless transmission to be sent so they would quickly release a pigeon with a quick message

Callum
So why would they use a pigeon, rather than the radio

Neil
He says that when an army unit was moving fast they might not have had time to put up an aerial and it would have been quicker just to release a pigeon with a message. Of course pigeons can be trained to fly back to a particular place

Callum
That’s right and in fact the military used over 250,000 pigeons to send messages during the Second World War

Neil
So what was the message that the pigeon was carrying

Callum
Ah, well, the truth is, they don’t know, they have no idea

Neil
What, even with all the power of modern computers and the best minds

Callum
Yes, here’s Gordon Corera again talking about the message. What word does he use to describe the process of understanding a code

Gordon Corera

They’ve been looking for a few weeks, the truth is that it was designed not to be cracked easily

Callum: What word does he use, Neil

Neil
He says the code was designed not to be ‘cracked’ easily. We use the verb ‘to crack’ when talking about codes

Callum
So, the code is designed not be cracked easily. Let’s hear a little bit more about what kind of code it might be. Here’s more from the BBC’s Gordon Corera who mentions one of the ways this code might have been created

Gordon Corera

One is using something called a one-time pad which is a technique where you apply a random key to a code and if you keep that secure and it’s truly random, it is basically unbreakabl

Callum
What kind of code is he talking about here

Neil
A code created with what’s called a ‘one-time pad’. As I understand it, if you think of a code like a lock, what do you need to open a lock

Callum
Well you need a key to open a lock

Neil
That’s right, and if you don’t have the key and there is no record of what the key was like or who made it or where it was kept, you’re going to have a problem

Callum
You won’t be able to open the lock

Neil
Exactly. With a code created with a one-time pad there is only one key and it’s only used once. After that, it’s destroyed. Without the key you can’t crack the code – it’s an uncrackable or unbreakable code

Callum
Gordon said that key should be random

Neil
That’s right. If something is ‘random’, it means there is no pattern to it. It’s not predictable or repeatable. And, if the key is truly random they’ll never be able to crack the code

Callum
Unless they find the key! And that’s what they are hoping. Gordon Corera again. What information are they hoping to find to help them

Gordon Corera

What they are saying is without more contextual information, basically who the sender was who the recipient was, when it was sent and exactly the identity of the pigeon it may be impossible to crack it

Callum
So what extra information are they looking for

Neil
They really need to find out who sent the pigeon, to whom it was sent and even the identity of the pigeon itself. That information might help them locate the key. So I guess for the time being, the pigeon message will remain a mystery

Callum
Well, perhaps not

Neil
What do you mean

Callum
Well a man in Canada heard this story and he thinks he’s got the code book to crack the message and he says it a much simpler code than has been thought

Neil
Really

Callum
But unfortunately, we don’t have time to go into that now, but there is a link to the story on our webpage

Time now for the answer to the question. Who is the first person recorded using written codes to keep his or her communications secret? Neil, you said…

Neil
I said King Harold in England

Callum
And the correct answer is actually Emperor Julius Caesar. And there’s in fact a Caesar Cipher, which is a kind of code which is attributed to Julius Caesar. It’s a very simple one actually, that each letter is just moved three places along. So, instead of writing ‘A’, he wrote ‘D’. And instead of writing ‘B’ it would have been ‘E’. So perhaps not a particularly difficult code to crack. These days, anyway. Well, that’s all from us today. Thank you very much Neil, goodbye

Neil
Goodbye

امیدوارم از پادکست انگلیسی BBC - کبوتر نامه بر لذت برده باشید.

گوش دادن به پادکست روش خوبی برای تقویت مهارت شنیداری و هم چنین یادگرفتن کلمات در بستر یک موضوع خاصه که این به تقویت مهارت مکالمه انگلیسی نیز کمک زیادی می کنه.

اگه تو هم از اون آدمهایی هستی که از گوش دادن به پادکست لذت می بره برات یه خبر خوب دارم! آموزشگاه زبان انگلیسی ۲۴talk یه دوره طراحی کرده مبتنی بر پادکست و داستان کوتاه به اسم "پادکستوری - Podcastory". این دوره سعی کرده یادگیری زبان انگلیسی رو مناسب با نیاز و سطح زبان آموز به یه فرایند بسیار مفرح، موثر، سریع و کم هزینه تبدیل کنه.

همین الان می تونی با کلیک روی عکس زیر و ثبت نام در دوره ی آموزش زبان انگلیسی با پادکست و داستان ۲۴talk اولین و مهم ترین قدم رو برای یادگیری زبان انگلیسی برداری. وقت رو از دست نده!

دوره پادکستوری آکادمی مجازی ۲۴talk