Second Language Acquisition
Faculty of Graduate Studies
Using Mean Length of Utterance as a Measure for Young Learners' Language
Development in SLA
By:
Manal Kamel Abu Qwieder
Std. No: 21719083
Supervised by:
Dr: Raghad Dweik
Gmail: manal.kamel876 @ gmail.com
2018/2019
USING MEAN LENGTH UTTERANCE AS A MEASURE FOR YOUNG LEARNERS' LANGUAGE
DEVELOPMENT IN SLA
Abstract
This study aims to investigate learners' language development using MLU as a measure for
this purpose. Mean Length Utterance (MLU) is a quantitative measure for morpho-syntactic
complexity. Two sets of data were analyzed, from the utterances of two students one from
private school and the other from public school. The results reveal that, the student from the
private school is more advanced, linguistically, than her counterpart. Finally. Some
recommendations are considered in order to improve learners' language development.
Key words: mean length of utterance, learner's language development, curriculum, private
school, public school.
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USING MEAN LENGTH UTTERANCE AS A MEASURE FOR YOUNG LEARNERS' LANGUAGE
DEVELOPMENT IN SLA
Using Mean Length of Utterance as a Measure for Young Learners' Language
Development in SLA
Introduction
Second language acquisition is a complex process, involving many interrelated factors. For
child to acquire language he/she proceeds into stages; the initial stage is often referred to as the
one-word stage, because there is no word combination. After that, the child begins to combine
words, and then produces sentences. As children’s utterances .become longer, it is appropriate
for researchers to have a measure to determine complexity. A higher value of the MLU means
that a child is capable of producing more complex sentences. Which indicates more
development in acquiring. Mean length of utterance (MLU) is the standard measure to use for
this purpose.
Objective of the Study
This study aims to investigate the differences between two learners' language development
according to the curriculum used in their schools. Both aged eight years and in the second grade.
One from private school, and the other from public school. Mean length of utterance (MLU) is
the standard measure to use for this purpose.
Questions of the Study
The study aims to answer the following questions
1- Are there differences between learners' language development, according to the
curriculum used at schools?
2- Is there an influence of MLU on learners' language development?
Literature Review
Mean Length of Utterance
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USING MEAN LENGTH UTTERANCE AS A MEASURE FOR YOUNG LEARNERS' LANGUAGE
DEVELOPMENT IN SLA
MLU was first developed by Nice in 1925 for calculating in words per utterance. Since
(Brown, 1973) as Allen, S. & Dench, C. (2015) states, however, "It has typically been
operationalized as the mean number of morphemes per utterance (MLUm) in 100 consecutive
but non-repetitive utterances in a spontaneous speech interaction". (Ranti, A. 2015) states that,"
Mean Length of Utterance (MLU) is a quantitative measure for morpho-syntactic complexity.
It indicates how many morphemes or words a child uses per utterance". This measurement has
been shown to be a remarkably useful index of grammatical development among normal
children, at least up to a mean length of 4.0, primarily because increases in utterance length
reflect the acquisition of new knowledge (Ranti, Ibid). In other words, a higher value of the
MLU means that a child is capable of producing more complex sentences. Roger Brown first
added the insight that counting morphemes rather than whole words was a more sensitive
approach to grammatical development (Brown, 1973). Also (Gass, S &, Selinker, L. 2008)
believe that "Mean Length Utterance (MLU) is the standard measure used". (Ranti, ibid) says,
"Morphological development is analyzed by computing a child’s Mean Length of Utterance
(MLU). Usually, a sample of 50 to 100 utterances is analyzed to draw conclusions about the
child’s overall production." increases in utterance length reflect the acquisition of new
knowledge. Each word a child produces is broken down into morphemes. The definition of a
morpheme is “a minimal unit of meaning or grammatical function” (Yule, 2006: 63). J, F,
Miller. & R, S, Chapman. (1981) state that, "Age-appropriateness can be determined for a
child's MLU. One caution is that MLU is only a general indicator of language structural
development and should not be used as a sole basis for clinical decisions". Another study by
M, L, Rice. S, M, Redmond. & L, Hoffman. (2006) said that," MLU is a reliable and valid
measure of language development for longitudinal growth patterns from 3 to 8 years of age".
Stork and Widowson as cited in Rante. 2015 states that Morphemes can be classified into
two categories; they are bound morphemes and free morphemes. Free morphemes are
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USING MEAN LENGTH UTTERANCE AS A MEASURE FOR YOUNG LEARNERS' LANGUAGE
DEVELOPMENT IN SLA
meaningful units of language structure, which can be used independently, or in combination
with other morphemes. A word, which consists of only one morpheme, must consist of free
morpheme. Moreover, they are divided into two types: lexical morphemes and functional.
Meanwhile, bound morphemes are meaningful units of language structure, which can only be
used in conjunction with other morphemes. Moreover, they are divided into two types:
inflectional morphemes and derivational. (Stork and Widowson, 1983: 79,) as cited in (Ranti,
A.2015).
Calculating Mean Length Utterance
Although MLUm is very widely used, calculating it poses a number of difficulties. These
include determining morpheme productivity, applying morpheme-counting rules across
languages, and the time and effort required to calculate MLUm.
Brown specified that a language sample of 100 utterances should be used to compute the
MLU. Repetitions of phrases or words should only be counted once, unless the word is repeated
for emphasis. Filler words, as in umm or oh, should not be counted but no, yeah, and hi are
counted as one morpheme each. Compound words that are made up of two or more free
morphemes are counted as single words (e.g. birthday, choo-choo, and night-night count as one
morpheme each). Diminutives (e.g. mommy, doggie), irregular past tense verbs (e.g. got, went),
and catenatives (e.g. gonna, wanna, hafta) are counted as one morpheme. All inflections, such
as possessive-s, plural-s, third person singular-s, regular past-d, and progressive-ing, are
counted as separate morphemes (e.g. her counts as one mor0pheme whereas hers counts as two
morphemes).
Brown also, stated the formula of counting the MLU;
Mean Length Utterance = Number of morpheme
———————
Number of utterances
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(Brown. 1973)
USING MEAN LENGTH UTTERANCE AS A MEASURE FOR YOUNG LEARNERS' LANGUAGE
DEVELOPMENT IN SLA
(Brown. Ibid) describes five stages of morphological and syntactical development. These
stages have a correlation with age. When the child moves from stage to stage, his grammatical
development will increase.
Methodology
Two sets of data were analyzed, each set consists of thirty utterances, gathered from
spontaneous speech among description of some pictures, between the two learners and their
investigator. MULm was used as a tool to draw conclusions about their performance.
Data analysis
The aim of this study is to measure the learners' language development using MLU as a
tool for this purpose. Accordingly, the data were transcript in order to calculate the MLU of the
students' utterances.
Table.1-Sample of analyzing utterances of the learner from private school.
Student's utterances
Morphemes
Morphemes number
I can see a bus
I-can-see-a-bus
5
Sami feed the animals
Sami-feed-the-animal-s
5
He sweep the floor
He-sweep-the-floor
4
She makes the beds
She-make-s-the-bed-s
6
Mary is helpful and Sami Mary-is-helpful-andis clever
7
Sami-is-clever
Table.2-Sample of analyzing utterances of the learner from public school.
Student's utterances
Morphemes
Morphemes number
He like fish
He -like-fish
3
Birds leg two…has
Bird-s-leg-two-has
5
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USING MEAN LENGTH UTTERANCE AS A MEASURE FOR YOUNG LEARNERS' LANGUAGE
DEVELOPMENT IN SLA
There are three bird
There-are-three-bird
4
Sami iron the cloth
Sami-iron-the-cloth
4
This is eye
This-is-eye
3
The above two tables indicate that there was a difference between the MLU of both
learners. As a result, there was a difference between them in their language development.
The following table show the results of the statistical analysis of the whole data.
Student
Total number of Total of morphemes Mean of (MLU)
utterances
in all utterances
The student from 30
242
5.80
private school
The student from 30
131
4.36
public school
The results of the above table show that, MLU of the student from the private school is
longer than the MLU of student from the public school, therefore, there was an obvious
difference between both learners in their language development.
Discussion and Results
The results of the study demonstrate that, MLU influences learners' language development.
Which was obvious in their utterances. For example, when the student from the public school
said," this is eye" get credit for 3 morphemes. However, if she said, "this is an eye" she would
get 4 morphemes. Also short MLUs indicates delay in the grammatical markers. However, that
is obvious in many utterances of the learner from the public school. For example, when she
said," Sami iron the cloth" instead of "Sami irons the clothes" she didn’t use the third person
marker "s". In addition, she did not use the plural marker. Another closer look for table 1, we
can notice that even the student from private school has many grammatical mistakes. When she
said, "Sami feed the animals" and "he sweep the floor", she did not use the third person marker
in both sentences. On the other hand, she use the same grammatical rule when she said," she
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USING MEAN LENGTH UTTERANCE AS A MEASURE FOR YOUNG LEARNERS' LANGUAGE
DEVELOPMENT IN SLA
makes the beds". This indicates that, her language is more advanced than the language of the
other student. In other words, the more to produce morphemes the more to develop in language.
This result is correspond to Fowler, A .(1986) study, who said that "the mean length of an
utterance is a good indicator of the kind of morphological and syntactic structures a child has
acquired and is prone to use". Moreover, we can notice that the longest utterance that the student
from the public school produced was 5 morphemes only, whereas, the student from the private
school produced an utterance consist of 7 morphemes. As a result, here language is more
developed.
After careful investigation for the MLU analysis, one can conclude that the curriculum used
in both schools has an important role and effect on their language development. If we compare
both curriculums in two schools, we find that although both of them have the same objectives,
there are a big difference in the learning styles and strategies used in the teaching process in
each school. According to the private school, the curriculum was designed in a suitable way to
fit the needs of the learners, and the teachers use many strategies to achieve this purpose. They
teach the rules of grammar through communicative approaches, for example; they use taskbased activities in the classroom, also advise their students to watch films, videos, and to read
newspapers outside the classroom, in order to extant their exposure to the language. On the
contrary, in the public school, the teachers teach the curriculum in the traditional way, they
focus on forms rather than meaning, with limited exposure to the language in the classroom.
Therefore, their language development is limited. Therefore, the results show that MLU is a
valid and reliable measure for language development, which corresponded with the results that
showed by (M, L, Rice. S, M, Redmond. & L, Hoffman. 2006) who said that," MLU is a reliable
and valid measure of language development for longitudinal growth patterns from 3 to 8 years
of age".
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USING MEAN LENGTH UTTERANCE AS A MEASURE FOR YOUNG LEARNERS' LANGUAGE
DEVELOPMENT IN SLA
Conclusion
MLU can be used as an identification measure of general linguistic development. Besides,
offering the advantages of being quick and simpler to analyze. However, it was emphasized
that the use of MLU provides more efficiency in the characterization of linguistic development.
The study in hand reveals that, The MLU of the utterances of the learner from the private school
was (5.8), whereas, the MLU of the student, from public school, was (4.36). Although in some
cases the differences were small, the girl from the private school outperformed her counterpart
in production of all target structures. This fact demonstrates that, student from the private school
is more advanced linguistically than her counterpart from the public school. This development
was reasoned for many factors; among them was the curriculum and the way in which it was
offered. Consequently, these results reveals that, there are differences between learner's
language developments, according to the curriculum used at schools. Furthermore, there is an
influence of MLU on learner's language development.
Recommendations
In order to develop learners' language, teachers need to increase sentence length, by
determining what is missing from the learners' speech. Increase their vocabulary, For example.
Their vocabulary should include nouns, verbs, adjectives, possessives, negatives,
demonstratives, and question words. Also. Learners with short MLU are often delay at their use
of these grammatical rules. Consequently, teachers should focus on meaning rather than forms.
They should follow the new strategies and approaches in teaching in order to improve their
grammatical rules. Finally, this study was limited in time and participants. Moreover, the period
of investigation. Therefore, further studies, with a larger sample and deep investigations, should
be considered.
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USING MEAN LENGTH UTTERANCE AS A MEASURE FOR YOUNG LEARNERS' LANGUAGE
DEVELOPMENT IN SLA
References
Allen, S. & Dench, C. 2015. Calculating mean length of utterance for eastern Canadian
Inuktitut. University of Kaiserslautern, Germany.
Brown, R. 1973. A first language: the early stages. Cambridge, Mass.: Harvard University
Press, https://scholar.google.com/scholar
Fowler, A, E. 1986.The Development of Language Structure in Children with Down syndrome.
HASKINS LABORATORIES: Status Report on Speech Research
Gass, S, M & Selinker, L (2008). Second Language Acquisition. An introductory course. Third
edition. Taylor & Francis
J, F, Miller. & R, S, Chapman. (1981). The relation between age and mean length of utterance
in morphemes. Journal of Speech, Language, and Hearing Research, 24(2), 154-161.
M, L, Rice. S, M, Redmond. & L, Hoffman. (2006). Mean length of utterance in children with
specific language impairment and in younger control children shows concurrent validity and
stable and parallel growth trajectories. Journal of Speech, Language, and Hearing Research,
49(4), 793-808. Doi: 10.1044/1092-4388(2006/056)
Ranti, A. 2016. Mean Length Utterance of Children Morphological Development.
https://www.researchgate.net/publication/311571150
Yule, George. 2006. The Study of Language. New York: Cambridge Univ. Press.
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