The understanding of second language (L2) speech is increasing in importance for researchers and practitioners in linguistics, psychology, education, speech-language pathology, and computer science due to the growing contribution of research on non-native language acquisition to models of human language and cognition. The present volume provides a state-of-the-art overview of non-native speech research including in-depth discussion of theoretical frameworks and experimental studies. Given our training and intellectual orientation, the book is situated within laboratory phonology, which draws on a variety of fields including theoretical and experimental phonetics and phonology. What unites research within this approach to the study of human speech is its experimental orientation. To the greatest extent possible, we have kept discussion theory-neutral so as to make the book accessible and of interest to the widest audience possible.

In writing this volume, we have had two main objectives and two principal target audiences. As concerns the former, we wished to offer the reader an in-depth introduction to the major L2 speech research themes and questions, the theoretical frameworks and methodologies used to investigate these, and, finally, the rich range of experimental research that has been conducted on a vast array of topics. We also wanted to produce a research manual that would provide present and future researchers with the practical tools and some of the experience necessary for conceptualizing an experiment, formulating research hypotheses, designing an experiment to test these hypotheses, and analyzing the results. In terms of target readership, we have written for two main groups – for young researchers new to the scientific study of L2 speech and, potentially, less familiar with experimental research, as well as seasoned language acquisition specialists wishing to understand or undertake research on non-native speech perception and production for the first time. We have assumed that both groups of readers will have a basic background in phonetics, particularly acoustics, phonology, and statistics. However, all core concepts and phenomena are defined with illustrating examples the first time that they are encountered.

Existen varios tipos de programas educativos en los EE.UU. que emplean la lengua española. Algunos son para niños que todavía no saben el inglés, a quienes se les suele referir como “English Language Learners” (ELL) o aprendices del idioma inglés (AII). De estos, hay programas que tienen como única meta la preparación de los estudiantes para las aulas que imparten la instrucción totalmente en inglés. Otros buscan promover el mantenimiento y el desarrollo del español. También existen programas para estudiantes de todas las edades que quieren aprender el español como segunda lengua. En este capítulo, repasamos la historia y la trayectoria de la “educación bilingüe,” así como varios tipos de programa que enseñan el español a diferentes tipos de estudiantes en los EE.UU.

Aspectos históricos de la educación bilingüe en los EE.UU.

Bien se sabe que los EE.UU. es un país fundado y, posteriormente, poblado por numerosos grupos de inmigrantes provenientes de todas partes del mundo. Durante la época colonial, llegaban principalmente hablantes del inglés, de alemán, de francés, de español y de holandés. A partir del siglo xix y especialmente desde principios del siglo xx llegaron grandes olas de inmigrantes de todas partes de Europa.

Muchos de estos grupos establecieron sus propias escuelas.

As we mentioned in Chapter 1, children normally manage to learn to understand and speak the language around them. Adults, on the other hand, struggle to do the same thing when the language is acquired later in life. This difficulty is obvious in L2 learners’ productions. Most of us have encountered some infelicitous situations, first or second hand, resulting from our not being able to distinguish different vowels or consonants in someone's speech. For example, think of the word election produced by some Japanese-speaking learners of English or the words sheet, beach or fact pronounced by certain Spanish- or Portuguese-speaking learners of English. These instances of L2 speech would normally just spark a few giggles among native speakers but can sometimes lead to awkward or embarrassing moments for those who produced them.

Having discussed the major research questions and theoretical concepts that underlie the study of L2 speech in Chapters 1 and 2 respectively and then the research methodologies used to investigate such questions and models in Chapter 3, we now turn to Part III, Case studies and analysis of L2 Speech perception and production. This chapter and the four that follow showcase the most representative empirical studies that have focused on the L2 acquisition of vowels, obstruents, sonorants, sequences, and prosody. In this chapter, we will focus specifically on studies that have investigated the L2 acquisition of vowels in perception and production, with an emphasis on those studies where a Romance or Germanic language was the L1 or TL.

This chapter begins with a phonological and phonetic description of vowels (§4.1), with English and Spanish vowel systems discussed as examples. The phonetic description will include the main acoustic cues that distinguish vowels, namely formant frequencies and vowel duration. Before presenting cases of L2 vowel perception and production, we will summarize those parts of Chapters 2 and 3 that apply to research on L2 vowels. Specifically, we will provide a brief summary of the theoretical models that have inspired most L2 vowel studies and the typical methodology that they use (§4.2).

One of the consequences of the globalization of the world in which we live is the ubiquitous presence of multilingualism and the increasing need to learn multiple languages. In this book, we have focused on one particular aspect of this multilingualism, namely, the acquisition of the sound system of a non-native language. Our discussion was guided by two general objectives. First, we wished to offer you, the reader, an in-depth introduction to the major L2 speech research themes and questions, the theoretical frameworks and methodologies used to investigate these, and, finally, the rich range of experimental research that has been conducted on a vast array of topics. All of this was done paying attention to the key concepts and frameworks in phonetics and phonology necessary to understand this research. Our second objective was to produce a manual that would provide present and future researchers not only with the required theoretical and empirical background but also the intellectual and methodological tools necessary for conceptualizing an experiment, formulating research hypotheses, designing an experiment to test these hypotheses, and analyzing the results. Indeed, all of the chapters in this book have had both a theoretical and practical component.

Here, we will review the main themes and findings of each chapter in order to provide a succinct overview of L2 speech research to date (§9.1.1). We will also highlight topics that received little or no attention in the preceding chapters (§9.1.2). We then turn to future research, first discussing some promising technologies (§9.2.1) as well as alternate data sources, then possible areas and research questions for future L2 speech research (§9.2.2).

An overview of past L2 speech research

Having reached this point in the book, you are now aware of the range of acquisition topics, L1–TL pairings, and phonetic and phonological structures that have been previously studied. In order to draw out the major themes covered, including similarities between chapters, we will first review the main themes and findings discussed in this book (§9.1.1), then turn to several topics that received little attention but that very much merit study.

Second language instructors as well as students approaching the study of second language acquisition are usually fascinated by the differences between native and L2 speakers. In pedagogical and applied linguistic texts, it is not uncommon to find detailed lists describing the ways in which the segmental and prosodic aspects of L2 speech differ from TL norms. Although such information is useful, it does not allow us to explain the behaviour of L2 learners. Having read Chapter 1, you are now familiar with many of the major questions that people have asked and continue to ask concerning L2 phonetic and phonological learning. Based on your own experience as an L2 learner or as someone who has regular contact with non-native speakers of your L1, you may have your own set of questions for which you would like to find answers. The goal of L2 speech research is to answer such questions. Setting out to do so may seem intimidating – where should you start? What is the best method for coming up with valid answers? Fortunately, we are almost never starting from zero. As is the case with all scientific research, it is rare to investigate a topic that has not been previously studied to some extent, perhaps with another language pairing or a different segmental or prosodic structure. The sum of all previous research is a treasure trove for researchers – as the physicist and mathematician Isaac Newton said, like many others before him, we stand on the shoulders of giants. In simple English, we have access to the reflections and research findings of others that can be used to structure and guide our own scientific investigation. As we will see in this chapter, one of the main ways in which this is done is through the theoretical concepts and frameworks that previous researchers have developed to formalize their own intuitions and research findings as well as those of others.

In our daily life, we regularly encounter phenomena that make us ask the question Why? For example, you may currently be learning a second language and find that certain sounds are more difficult to perceive or produce than others, or that, while you can produce these sounds accurately in isolated words, you are less accurate in more fluent speech. Why are some sounds harder to perceive and produce than others? Why does context affect accuracy? Alternatively, you may be someone who regularly interacts with non-native speakers and have noticed how much variability exists in people's pronunciation. What are the sources of this variability? Are there factors beyond learners’ L1s and previous learning experiences that can explain these differences?

In this chapter, we will discuss in detail how one can go about answering such questions in a thorough, scientific way via experimental studies. As we will soon see, this involves transforming our questions into testable hypotheses, creating one or more tasks with controlled stimuli, collecting data from an appropriate group of native and non-native speakers of the language of interest, then analyzing and interpreting the results with reference to theories and to previous research. All of this is done as part of the scientific method, which we discuss next.

The scientific method and L2 speech research

While every discipline has its own particular theories and methodologies for data collection and analysis, all scientific disciplines share a common set of principles that structure the way in which research is carried out; this is referred to as the scientific method. This method involves a series of steps that are followed when you seek to answer a question concerning the nature of some phenomenon. The scientific method seeks to be rational – investigation is guided by reason as opposed to emotion; rigorous – research is in depth and is reliable, that is, it is possible to verify the results based on the procedures described; and systematic – there is a well-established protocol to be followed that makes clear what is and is not acceptable when studying a phenomenon.

If you are reading this book, you are likely a second/third language learner curious about her or his pronunciation, a linguist, psychologist, or other researcher interested in issues of bi/multilingualism and learning with a particular focus on speech, or both. Regardless of your interests, there are likely to be various aspects of your own speech or that of non-native speakers that have struck you and that you wish to understand better. In this book, we will investigate what is commonly referred to as foreign accent, the various differences between the speech perception and production of non-native and (sometimes idealized) native speakers. Our goal is to provide you with an understanding of the principles and phenomena of second language (L2) speech perception and production, theories that have been developed to model these, and the experimental methodologies used to investigate both segmental (i.e., consonants and vowels) and prosodic phenomena (e.g., lexical stress or tone, rhythm, intonation, and fluency). Our hope is that, once you have finished reading this book, you will either have answers to your questions from previous research or, perhaps more importantly, the ability to conduct your own studies.

In this first chapter, we lay the foundation for the discussion in the entire book, focusing on the major theoretical and empirical questions that guide L2 research, particularly as concerns the acquisition of phonetics and phonology (§1.3). Each theme will be introduced via a series of research questions to be explored throughout the book followed by the presentation of an illustrative study. However, before discussing these central themes of L2 speech research, we first examine the basic structure of speech (§1.1) and a number of concepts relevant to any study of L2 acquisition (§1.2).

The structure of speech

Human speech is the focus of two major branches of linguistics, namely phonetics and phonology. Traditionally, these two subdisciplines have been distinguished in terms of their orientation to the study of spoken language. Phonetics investigates the physical aspects of sound. These include its production (articulatory phonetics), transmission (acoustic phonetics), and perception (perceptual phonetics).