Shadowing Practice: What are Design Patterns? | Introduction to Design Patterns and Principles | Geekific - Learn English Speaking with Video

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What's up geeks and welcome to the channel! If you're in the computer science domain you definitely have heard of design patterns before or even used a few patterns in practice with or without your knowledge but really what are design patterns?
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why were they created in the first  place and who decided to create them?
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what is actually the main  purpose behind design patterns?
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all these questions and more will be answered  in this first video of our design pattern series to which later we will add more videos  detailing each pattern on its own.
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As always and to better understand  the concept at hand let's take a practical example and let's imagine a steak. You see I may have imagined a well done steak you may have imagined a medium done one someone else might have imagined a vegan steak, while ordering a steak at a restaurant,  each one of us orders it differently we don't all necessarily have to  order or eat our steak the same way and yet the cook that is preparing it, will take the same piece of  meat or soy in addition to the way or policy of how we like our steak and prepare a delicious meal a different one for each one of us using the same  piece of meat as a starting point To compare this to a computer program suppose  we have a Chef class with a prepare() method This method can take a WellDoneInstruction  object and in this prepare method the chef will know how to prepare a well-done steak but what about other ways of preparing a steak we will have to overload this method to take in  a MediumDoneInstruction and a VeganInstruction Okay now our chef knows how  to cook all the steaks we want Let's say this chef extended his knowledge and  now knows of five additional ways to cook a steak should we add five more methods? Well let me suggest something else, why not replace all these methods with a single  method that takes a steak cooking instruction and let all these classes inherit  this one what do you think?
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Isn't that a better design for our Chef class You see this way, our class is closed  for modification and open for extension which means that not only we won't  have to add any more methods nor even touch our Chef class in the future but in addition to this when a new instruction is needed all we have to do is extend the SteakCookingInstruction class  we created with this new instruction and the prepare method will  handle it automatically Now because of our design, this chef  apparently skyrocketed and decided to open a new branch for the restaurant So every time a new customer enters the restaurant the chef goes ahead and informs them  of the opening date and details for the new branch but do you think that is the best  approach to deal with such a scenario?
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Don't you think that instead of  waiting for people to come in the chef should have instead messaged  all his customers the details about the opening or even posted on social media and those interested would have showed up wouldn't his reach be far larger? In both previous scenarios the solutions I suggested hint at a specific pattern this pattern will not actually solve our problem and generate magically ready code for us but rather it will give us a description or template to follow a way of thinking  that will help us solve these problems like a series of formalized best practices, steps  that programmers have followed and used to solve common problems like the one we just encountered. Design Patterns best became known from the design patterns book by Erich Gamma, Richard  Helm, Ralph Johnson, and John Vlissides often referred to as the Gang of  Four book published in the mid 90s.
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Now, this book details 23 design patterns  which were split into three groups: Creational Patterns, Structural  Patterns, and Behavioral Patterns.
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Creational patterns deal  with the creation of objects Instead of you instantiating all  objects very specifically and explicitly they give you more flexibility  in how the objects are actually created Let's suppose that we have  a class with 10 attributes but not every time we create an object based on  this class we need to specify all 10 attributes sometimes you only need one, in other cases  three or two, and sometimes eight or nine, in such cases we are left with two  solutions and not quite the best out there: either to create a lot, like a lot, of  overloaded constructors for our class or create one constructor that takes  all arguments but then we will need to pass as null values the ones we don't  require upon creation of our objects Well, design patterns will tell  you wait, you have a third option follow the template provided  by the Builder Pattern, a template widely used and tested  by many developers out there Well if I were in your shoes  I'd pick this last option.
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Structural patterns deal with  how classes are actually designed with how things like inheritance  and composition and aggregation can be used to provide extra functionality Let's consider that in our application we are storing book objects and these books well there's too many of them, like in the hundred thousand books of a library, or the books in all of amazon online store, and for some reason we need to represent each book by an object You see in this case we will have a bunch of book objects that will share the same attributes and by bunch I mean in the thousands which will have the same author, the same amazon  physical storage location, same places it can be delivered to, same provider, etc. you got the idea and maybe the only attribute that will defer is the title itself and the price in some cases So why create for each book an object and consume all this amount of memory while at the same time if we follow the template specified by the Flyweight Pattern we will be able to minimize memory usage by sharing as much data as possible  between our similar objects You see that is what design  patterns are trying to do they are trying to provide us with a schema, a step-by-step definition or template to help us overcome development or architectural  problems that others have faced before us.
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Finally, Behavioral patterns are specifically  concerned with communication and assignment of responsibilities between  objects as the program is running The two examples we gave at the beginning  of our video can actually be solved using two different behavioral patterns one of them being the Strategy pattern Let's take a second example and  suppose we realized that the state of an object in our application will  be changed by a lot of other objects but we need to be able to undo the last change Well this can be done in many different ways and you are free to use any of them but there is a Memento design pattern that describes a simple proven approach. So to sum up, design patterns will speed up your development process by providing  tested and proven development models At first you may not notice that you require  the use of this pattern here or there or you may make use of it without even knowing but with time practice and hopefully with the help of our videos you will! So that's it for this video, I hope it was helpful, thank you guys for watching,  take care and I will see you in the next one!

Vocabulario y notas de pronunciación para esta lección

Esta lección de conversación de nivel C1 se basa en el vídeo “What are Design Patterns?”. Las palabras que más se repiten: pattern, object, design, steak, chef. Este vídeo tiene 11 frases y 1284 palabras para practicar shadowing. La parte hablada dura 7:17. El hablante habla a un ritmo natural de unas 176 palabras por minuto, cercano a una conversación cotidiana. El 85 % de las palabras está entre las 3.000 más comunes del inglés; conviene repasar el resto antes de empezar. 7 de sus 11 frases son preguntas, así que sirve para practicar la entonación de las preguntas y las respuestas cortas.

Vocabulario clave de este vídeo

Las 15 palabras más avanzadas del vídeo, con su pronunciación y significado:

PalabraPronunciaciónSignificado
steak sustantivo/steɪk/bistec, bisté
template sustantivo/ˈtɛm.plɪt/plantilla
attribute sustantivo/ˈæt.ɹɪˌbjut/atributo
behavioral adjetivo/bɪˈheɪvjəɹəl/del comportamiento, conductual
overload verbo/ˌəʊvəˈləʊd/sobrecargar
specify verbo/ˈspɛs.əˌfaɪ/especificar, circunstanciar
aggregation sustantivo/æɡɹəˈɡeɪʃən/agregación
formalize verbo/ˈfɔɹ.məlaɪːz/formalizar
instantiate verbo/ɪnˈstænʃieɪt/instanciar
magically adverbio/ˈmæd͡ʒ.ɪ.kli/mágicamente
skyrocket verbo/ˈskaɪˌɹɒk.ɪt/dispararse, ponerse por las nubes
inherit verbo/ɪnˈhɛɹɪt/heredar
programmer sustantivo/ˈpɹoʊɡɹæmɚ/programador, programadora
undo verbo/ʌnˈduː/deshacer, desfacer
geek sustantivo/ɡiːk/friki, flipado

Phrasal verbs que vas a escuchar

PalabraPronunciaciónSignificado
go ahead verbo/ˌɡoʊ əˈhɛd/venga, adelante
show up verbocomparecer, personarse
speed up verbo/spiːdˈʌp/acelerar, apurarse
sum up verbosumar

Gramática en este vídeo

Las estructuras que más usa el hablante, con las palabras exactas del vídeo:

EstructuraEn el vídeo
Oraciones condicionales if + oración, will/would + verbo — una condición y su resultadoif I were in your shoes I'd pick
“Used to” used to + verbo — un hábito o estado pasado que ya no es ciertoused to solve
Voz pasiva be + participio pasado — importa lo que ocurre, no quién lo hacewill be answered · is closed · were split
Present perfect have/has + participio pasado — una acción pasada que sigue importando ahorahave heard · have followed · have faced

Pronunciación a tener en cuenta

El hablante usa 8 contracciones y formas reducidas, como don't, I'd, isn't. Dilas en su forma corta, tal como las oyes.

  • Los sonidos de “sh” y “zh”: aggregation /æɡɹəˈɡeɪʃən/, instantiate /ɪnˈstænʃieɪt/, modification /ˌmɑdɪfɪˈkeɪʃən/
  • Palabras largas — cuida el acento: behavioral /bɪˈheɪvjəɹəl/, aggregation /æɡɹəˈɡeɪʃən/, modification /ˌmɑdɪfɪˈkeɪʃən/, inheritance /ɪnˈhɛɹɪtəns/, architectural /ˌɑɹkɪˈtɛkt͡ʃəɹəl/

Sonidos difíciles para hispanohablantes:

  • s + consonante al inicio — sin añadir una “e” delante: steak /steɪk/, specify /ˈspɛs.əˌfaɪ/, schema /ˈskiːmə/, skyrocket /ˈskaɪˌɹɒk.ɪt/
  • /v/ — no es /b/: los dientes tocan el labio inferior: behavioral /bɪˈheɪvjəɹəl/, overload /ˌəʊvəˈləʊd/, vegan /ˈviːɡən/
  • /z/ — sonora, no /s/: formalize /ˈfɔɹ.məlaɪːz/, minimize /ˈmɪn.ɪˌmaɪz/

Cómo practicar con este vídeo

  1. Escucha el vídeo entero una vez sin hablar y anota las palabras que no conoces.
  2. Empieza a velocidad 0,75×, haz shadowing frase por frase y vuelve a la velocidad normal cuando te resulte fácil.
  3. Grábate y compara con el original, prestando atención a palabras como steak, template, attribute.

¿Qué es la Técnica de Shadowing?

Shadowing es una técnica de aprendizaje de idiomas respaldada por la ciencia, desarrollada originalmente para la formación de intérpretes profesionales y popularizada por el políglota Dr. Alexander Arguelles. El método es simple pero poderoso: escuchas audio en inglés nativo y lo repites en voz alta de inmediato, como una sombra que sigue al hablante con solo 1-2 segundos de retraso. A diferencia de la escucha pasiva o los ejercicios de gramática, el shadowing obliga a tu cerebro y músculos de la boca a procesar y reproducir simultáneamente patrones de habla reales. Las investigaciones muestran que mejora significativamente la precisión de la pronunciación, la entonación, el ritmo, el habla conectada, la comprensión auditiva y la fluidez al hablar, convirtiéndola en una de las metodologías más efectivas para la preparación del IELTS Speaking y la comunicación en inglés en el mundo real.

Técnica de shadowing: lee la guía completa paso a paso →