Children maestro the elaboratenesss of their native linguistic communication before they are able to bind a knot, leap rope, or pull a decent-looking circle. This accomplishment is so everyday and so expected that most people seldom give it a 2nd idea. But its.significance has non been lost on linguists, who are merely excessively cognizant of the complexness of linguistic communication and of the enigmas that surround its acquisition. A cardinal dogma of virtually all research on linguistic communication acquisition is that the ability to utilize linguistic communication stems from the fact that, as kids, all normal human existences get a grammar-a cognitive system that determines the relationship between signifier and significance in all possible sentences of their linguistic communication. As it is presently understood, a grammar includes two major constituents ( see table 1.1 ) .The foremost is a vocabulary or ‘dictionary ‘ , which serves as a depository for information about the belongingss of single words ( e.g. , their signifier and significance, the types of elements with which they can or must happen, and so forth ) .
The 2nd constituent of a grammar consists of assorted systems of rules that regulate the linguistic communication ‘s sound form ( phonemics ) , the construction of its words ( morphology ) , and the signifier and reading of its sentences ( sentence structure and semantics ) . Working together, the different constituents of the grammar determine that in a sentence such as Sue ‘s female parent purchased several images of herself, the word female parent will be more to a great extent stressed than Sue ( puting aside the possibility of incompatible modulation ) ; that the verb purchase takes both a ‘subject ‘ ( matching to the buyer ) and a ‘direct object ‘ ( matching to the thing bought ) , that the topic precedes the verb ; that the verb precedes its object and that together they form a structural unit ; that the images depict Sue ‘s female parent ( non Sue ) ; and so away. Much of this information can be represented in the signifier of a tree construction, as depicted in ( 1 ) . ( Assorted inside informations, such as the internal construction of the NPs, are ignored here ; indexing represents coreference. )
There is good ground to believe that “ grammar ” instead than “ linguistic communication ” should be the focal point of research on lingual development. As suggested several decennaries ago by Bloomfield ( 1926:155 ) , a linguistic communication is “ the entirety of vocalizations that can be made in a address community. ” Since no 1 could of all time larn such an boundlessly big set of vocalizations, it follows that a linguistic communication per se can non be acquired. What can be acquired, nevertheless, is the finite grammar that allows members of a address community to understand and utilize their linguistic communication. Although I will go on to utilize the term ‘language acquisition ‘ for the interest of convenience and tradition, this book is concerned with the outgrowth of a peculiar cognitive sys- tem ( i.e. , the grammar ) , non a set of vocalizations. More specifically, it focuses on what is known about ‘syntactic development ‘ , the ( subconscious ) procedure whereby kids become able to organize sentences from words and other smaller structural units. Because of this focal point, it will frequently look that I am utilizing the footings ‘grammar ‘ and ‘syntax ‘ interchangeably ; in fact, of class, the syntactic system makes up, merely one portion of the grammar that is the merchandise of the linguistic communication acquisition procedure.
1. The Acquisition Process
Traditionally, the survey of grammar and the survey of linguistic communication acquisition have been conducted more or less independently of each other. This contrasts with the position adopted here, which is that the two types of research can and should be pursued as portion of a individual articulation endeavor. No grammatical theory can be considered satisfactory if there is no plausible history of how the grammars that it posits for peculiar linguistic communications emerge in response to see. ( N. Chomsky 1965:25 introduces the term ‘explanatory adequateness ‘ to depict this standard. ) By the same criterion, no theory of linguistic communication acquisition can be considered equal if it can non account for the outgrowth of the type of grammar believed to underlie grownup lingual competency. The acknowledgment that the terminal merchandise of ‘language acquisition ‘ is a grammar does more than merely set up a point of rule. It besides shapes and informs the survey of linguistic communication acquisition by casting visible radiation on the nature of the system that is acquired and the kind of informations to which scholars do — and do non — have entree. Let us briefly see each point in bend.
THE FINAL SYSTEM
It is by and large acknowledged that the mature grammar for any human linguistic communication is a complex and abstract system. There is ongoing contention about how to depict many parts of this system, and assorted phenomena continue to defy insightful analysis wholly. This is non to state that the being of a grammar is in uncertainty, or even that its belongingss can non be deduced with sensible certainty. Quite to the contrary, there is a near-consensus that ( the syntactic constituent of ) the grammar for any human linguistic communication must include both a set of classs such as ‘noun ‘ and ‘verb ‘ and a set of operations that can unite these classs to make an limitless figure of sentences with a peculiar linear and hierarchal organisation.
In add-on, a grammar must incorporate rules that regulate phenomena such as pronoun reading ( him can mention to John in John ‘s friends praised him, but non in John praised him ) and the relationship between a ‘gap ‘ and the ‘displaced ‘ component ( e.g. , a word ) with which it is associated ( comparison Who did you see a image of___ ? with* Who did a image of frighten you? ) . From the point of position of linguistic communication acquisition, so, it follows that we must happen a manner to explicate how linguistic communication learners discover classs such as ‘noun ‘ and ‘verb ‘ , how they determine the precise architecture of the phrases formed by uniting these classs, and how they come to hold peculiar restraints on pronoun reading and spread arrangement. In each instance, the more we know about the peculiar constituent of the mature grammatical system, the more exactly we can explicate hypotheses about the mental constructions and types of experience that are necessary for its development.
One of the more enigmatic disclosures of the grammar-oriented survey of linguistic communication acquisition has to make with the type of lingual ‘data ‘ available to kids. When linguists set out to detect the grammatical system of a linguistic communication that they do non talk, they constantly rely on alleged ‘grammaticality judgements ‘ — appraisals by native talkers of the acceptableness and reading of assorted existent and conjectural sentences. Imagine, for illustration, that a group of Chinese linguists analyzing English observed that some inquiry constructions contain two words. In order to find whether all combinations of whose words are possible, they would fix a list of conjectural sentences such as those in ( 2 ) – ( 6 ) and solicit judgements from native talkers of English.
( 2 ) Who saw what?
( 3 ) Who gave a gift to whom?
( 4 ) Who went where?
( 5 ) ? *Who went when?
( 6 ) *Who went why?
In order to prove subsequent hypotheses, they would do up farther sentences and look into their position, go oning in this mode until they had arrived at a successful state of affairs.
Analysis.
Children larning a first linguistic communication can non continue in this manner, nevertheless. As we will see in more item in portion II of this book, immature linguistic communication scholars neither petition nor receive judgements about the grammaticality of existent or conjectural sentences in their linguistic communication. Their exclusive beginning of information about the grammar that they must get is the normal, daily usage of linguistic communication by those around them. Although no linguist could build a grammar on the footing of such restricted informations, kids somehow win in making merely this.
2. The Acquisition Device
As we have merely seen, linguistic communication acquisition involves the outgrowth of a cognitive system incorporating classs and rules of a peculiar type. Much of this system exists subconsciously and is acquired without deliberate attempt at an early age. More surprisingly, this system develops even though kids do non hold entree to the type of grounds that bears most straight on its belongingss ( i.e. , grammaticality judgements ) . Taken together, these facts suggest that the human encephalon must incorporate a mechanism that is someway particularly suited for grammar- edifice and that is available from really early in life. For the interest of convenience, allow us mention to this mechanism as the acquisition device. The acquisition device can be thought of as a ‘function ‘ from experience to a grammar. That is, as depicted in figure 1.1, it takes as its input the type of experience that comes from being exposed to the linguistic communication in one ‘s environment and gives as its end product a grammar that permits productive usage of that linguistic communication. ( For early statements of this thought, see N. Chomsky 1966:20 and McNeill 1966:39 ; for some treatment, see McCawley 1976:171. ) In general, the survey of the acquisition device is oriented around two major research subjects, one affecting learn ability and the other development. The learn ability issue, besides called the ‘logical job of linguistic communication acquisition ‘ , is concerned with the type of acquisition device needed to build a grammar in response to the experience that is available during the first old ages of life.
The survey of development, on the other manus, focuses on the bit-by-bit outgrowth of grammatical forms and the types of mistakes that may happen prior to the attainment of mature lingual competency ( e.g. , Daddy prod and Me want that ) .These two research subjects have frequently been pursued independently ( for some commentary on this province of personal businesss, see Bowerman 1985:1259-60, 1987:443 ; and L. Bloom and Harner 1989:207-8 ) . However, both lines of enquiry are in fact closely related, since each seeks to understand the acquisition device, al- though from slightly different positions. Study of the learn ability job provides hints about the internal construction of the acquisition device, the type of grammar that it yields, and the type of experience that it requires. In contrast, probe of developmental phenomena outputs information about the real-time operation of the acquisition device in response to kids ‘s daily experience with linguistic communication. Put another manner, learn ability research focuses on how the acquisition device does what it does, while developmental research focuses on when it does it ( and why ) . Given their different ends and orientations, it is non surprising that the two attacks to linguistic communication acquisition draw on really different types of informations.
The survey of the learn ability job tends to do really limited usage of informations from child linguistic communication, trusting alternatively on debate affecting the relationship between the types of experience available to the acquisition device and the rules of grownup grammar that it must finally bring forth ( see fellows. 12-14 ) . In contrast, research into development draws really to a great extent on child linguistic communication informations both from realistic surveies and from experimental research ( table 1.2 ) . Naturalistic surveies of child linguistic communication involve the scrutiny of recordings and transcripts of kids ‘s self-generated address that have been collected over a period of months or even old ages. In contrast, experimental research efforts to measure kids ‘s cognition of peculiar construction types by holding them carry out a peculiar undertaking ( normally affecting comprehension, production, or imitation ) . Ex- perimental work is by and large cross-sectional, affecting the comparative survey of different groups of kids ( state, 2-year-olds and 4-year-olds ) at a peculiar minute in their development. On the other manus, realistic surveies tend to be longitudinal in that they track the development of a peculiar kid ( or group of kids ) over a period of clip.
1 Each type of survey has its advantages and disadvantages. Naturalistic surveies are able to look into address in an unstudied scene and are ideal for analyzing the bit-by-bit patterned advance of the acquisition procedure — as manifested, for in- stance, in the outgrowth of tense inflexion or pronominal instance, alterations in the rate of capable omission, or the addition over clip in the mean length of child- ren ‘s sentences ( alleged ‘mean length of vocalization ‘ or MLU ) . However, this type of survey is limited by the fact that certain constructions ( e.g. , passives or comparative clauses ) occur infrequently in self-generated address and are therefore hard to look into utilizing informations of this kind. Furthermore, because of their longitudinal character, realistic surveies are sometimes impractical due to the clip required to roll up informations.
3. Some Restrictions
The literature on linguistic communication acquisition is tremendous, thanks in big portion to the intense research activity of the past two decennaries. It goes about without stating that no book can purport to supply a comprehensive intervention of the field. In order to restrict the range of the present survey, several hard picks had to be made. First, it was necessary to take between a elaborate survey of the acquisition of a individual linguistic communication and a much more general overview of acquisition phenomena in several different linguistic communications. ( The ideal, of class, would be a elaborate survey of many different linguistic communications, but this is merely non a practical option — in portion because of spreads in the research literature and in portion because of restrictions on clip and infinite. ) As readers will rapidly detect, this book draws preponderantly on research surveies affecting the acquisition of English — this being the linguistic communication for which the presently available informations provide the most complete image of syntactic development. Occasional mention is made to the acquisition of linguistic communications other than English when relevant information is available, but no effort is made to study this portion of the acquisition literature in a systematic manner. Second, it was necessary to restrict the probe to a set of syntactic phenomena whose acquisition can be described in a coherent and comparatively self- contained manner. It was hence decided to except from the sphere of this book most issues refering to lexical belongingss of words ( intending and sub classification ) , morphology, and talk about even though these phenomena clearly play a function in sentence formation. The resulting image of the linguistic communication acquisition procedure will therefore of necessity be uncomplete, but hopefully non distorted.
Third, because of the big figure of surveies on syntactic development, it was necessary to be slightly selective in reexamining the relevant research literature. In portion for practical grounds, it was decided to concentrate on surveies that have appeared in the published literature. ( In add-on to their handiness, these surveies have the advantage of holding been filtered through the equal reappraisal procedure. ) However, where warranted, occasional mention is made to research that has appeared merely in thesiss and conference presentations. Still another hard determination had to make with the pick of theoretical frame- work. A good trade of work on development is formulated within the grammatical model known as ‘Government and Binding ( GB ) theory ‘ ( besides called ‘Principles and Parameters theory ‘ ) .
However, since the findings of these surveies do non in general entail the rightness of GB theory ( or any other model ) , I thought it advisable to repeat them in more ‘theory-neutral ‘ footings. I have followed this policy every bit closely as possible throughout my study of the developmental facts, maintaining formalism to a lower limit and using syntactic representations that are compatible with ( or at least easy translated into ) a assortment of modern-day theories. The theoretical treatment that dominates the 2nd portion of this book requires a different attack, since many of the proposals considered there are inextricably linked to GB theory. In order to suit this fact, I have devoted an full chapter to a reappraisal of work on the learn ability job within this model. However, a subsequent chapter lineations assorted options to the GB attack to larn ability, although these options are well less developed and less embracing in their range.
Within the restrictions merely outlined, the treatment of syntactic development contained in this book seeks to be as comprehensive and nonsubjective as possible. Facts and proposals from a broad assortment of beginnings are brought together and integrated in an effort to supply a consistent lineation of how the acquisition device is structured and how it operates. Of class, of import spreads remain, and many of the proposals I make may turn out controversial, but possibly it is non excessively much to trust that this exercising will lend to farther progresss in the field of linguistic communication acquisition research. A restriction common to all methods for the survey of syntactic development is that they are likely to undervalue topics ‘ existent competency: the fact that kids fail to bring forth or grok a peculiar construction or a peculiar sentence type in an experiment does non let one to reason with certainty that they lack the relevant grammatical cognition.
A assortment of immaterial factors- including inattention, nervousness, treating restrictions, and a failure to understand what is expected — can interfere with kids ‘s ability to utilize linguistic communication to the full extent of their grammatical capablenesss. It is hence possibly non surprising that the development of of all time more refined techniques of informations aggregation in recent old ages has resulted in consistent downward alterations in estimations of the age at which assorted mileposts in syntactic development are achieved. In subsequent chapters, we will hold juncture to see concrete cases of the jobs and defects of the assorted types of informations aggregation in more item. For now it suffices to observe that despite these restrictions, work on each of the two major research subjects in the survey of linguistic communication acquisition ( i.e. , learn- ability and development ) has yielded of import consequences in recent old ages. It is the end of this book to analyze these consequences in every bit comprehensive a mode as possible, with an oculus to casting visible radiation on the construction and operation of the acquisition device. Where possible, findings from different surveies are brought together to give a synthesis ; where this is non possible, note is made of the contradictory consequences and unresolved jobs that must expect future declaration.
Decision
Part I of this book is devoted mostly to a study of the developmental facts, concentrating on the stairss or ‘stages ‘ that linguistic communication scholars pass through on the manner to geting the grammar of their linguistic communication. These chapters discuss phenomena that are by all histories cardinal to the sentence structure of human linguistic communication — category assignment, word order, passivization, inquiry formation, relativization, and pro- noun reading, to call a few. The outgrowth of these phenomena is considered in approximative chronological order, get downing with kids ‘s first crude vocalizations and stoping with complex syntactic forms of assorted kinds. To the extent possible, these chapters present a historical overview of the relevant research literature and qualify the known facts in a comparatively theory-neutral manner. Although explanatory proposals are considered from clip to clip, no general theory of development is put frontward, and merely rather conservative premises are made about the grammar whose outgrowth is reflected in the development.
