Computer-assisted learning of Croatian language stress system (CAL-CROLESS)
Nives Mikelić, Tomislava Lauc, Kruno Golubić
Department of Information Science, Faculty of Philosophy
University of Zagreb
I. Lučića 3, Zagreb, Croatia
nmikelic@ffzg.hr, tlauc@ffzg.hr, kgolubic@ffzg.hr
Abstract. The aim of the paper is to present the computerassisted learning of Croatian language stress system as a base
for the development of the computer-assisted Croatian
ortography learning system. The system includes two main
modules: the dictionary and the rule list for stress assignment
and stress realization in Croatian. It is possible to use it for
knowledge pretesting, learning and final testing of the
acquired knowledge. Two different learning approaches were
taken: one was based on acquiring the knowledge concerning
the word-stress patterns that determine the word-stress
assignment, and the other was sample-based learning. The
goal was to probe the fruitfulness of both methods for dealing
with a stress assignment problem for Croatian.
I. INTRODUCTION
Until recently, computer-assisted language learning
(CALL) was a topic of relevance mostly to those with a
special interest in that area. Today, the majority of
language instructors must now begin to think about the
implications of computers for language learning. In the
practice courseware the computer serves as a vehicle for
delivering instructional materials to the learner. It is proved
that repeated exposure to the same material becomes
beneficial or even essential for learning. This makes
computer ideal for carrying out repeated exercises, since it
does not get bored with presenting the same material and
can provide immediate feedback. A computer can also
present such material on an individualized basis, enabling
learners to proceed at their own pace. Multimedia
technology integrated with the computer assisted learning
allows the different media (text, graphics, sound,
animation, and video) to be accessed on a single machine.
This creates a quite authentic learning environment,
whereas skills are easily integrated since the variety of
media make it natural to combine reading, writing,
speaking and listening in a single activity.
Although widely used for English and many other
languages, computer-assisted language learning is not
much applied to Croatian language yet. There is some
software for Croatian language beginners who want to
learn basic phrases, colors, numbers, food, shopping, time
etc published in English, but CALL-CROLESS is a
pioneer in the application of this technology to Croatian
orthography, especially to Croatian language stress system.
The reason why we developed the CALL-CROLESS is
given in the next section.
II. MOTIVATION
How important is the stress in Croatian language? A small
number of words in Croatian have no stressed syllable of
their own (most prepositions and the word “ne” (not) in
front of a verb are proclitics and hang on to the next word;
certain pronoun and verb forms are enclitics, hanging on to
the previous word. Apart from these, every word form has
one stressed syllable (some compound words have more
than one). Croatian language has three dialects (stokavian,
cakavian and kajkavian) and they differ significantly in the
stress realization. Stress does not differ only across local
dialects, but even across idiolects. It is the primary
distinguishing feature by which we can recognize the origin
of a speaker. Stressed syllables are called either rising or
falling, and contain a long or a short vowel. Traditional
notation in grammars and dictionaries combines these two
features, using four stress marks: short falling \\, long falling
^, short rising \ and long rising ⁄. The names of the stress
marks suggest a pitch change on a given syllable. Pitch
ascends within long rising stressed vowels, and drops during
long fallings.
Most of the native speakers of Croatian can tell a long
stressed vowel from a short vowel, but don't reliably
distinguish rising from falling. They also tend not to shift the
lexical stress from one syllable to another when making
different word-forms. Thus, the error in accentuation can
lead to misunderstanding. That was one of the reasons to
build a computer system for improving learning of Croatian
language stress system. The other important reason was to
investigate the results the learners achieve regarding their
linguistic background and native dialect.
It has been proved that the learners’ motivation and interest
raise even if they do a typical fill-in-the-gap exercise on the
computer rather than if they do it on a piece of paper or a
book.
In a way, doing tests in this form implies giving traditional
exercises a new format and results in a quite successful
experience, since learners enjoy the mere fact of being
manipulating computers. Besides, computer allows us to
give exercises a more attractive aspect by means of colour,
different letter styles, pictures, graphs, etc. Therefore, we
tried to develop the CALL for Croatian stress system,
considering the importance of presenting it in a visual way.
So, how important is the stress in Croatian language?
Croatian language has three dialects (stokavian, cakavian
and kajkavian) and they differ significantly in the stress
realization. Stress does not differ only across local dialects,
but even across idiolects. It is the primary distinguishing
feature by which we can recognize the origin of a speaker.
Most of the native speakers of Croatian can tell a long
stressed vowel from a short vowel, but don't reliably
distinguish rising from falling. They also tend not to shift
the lexical stress from one syllable to another when making
different word-forms. Thus, the error in accentuation can
lead to misunderstanding. That was one of the reasons for
building a system to ease the learning of Croatian language
stress system. The other reasons was to investigate the
results that learners achieve regarding their linguistic
background and native dialect.
III. SYSTEM DEVELOPMENT
A. Phase 1.
CAL-CROLESS is the computer-assisted learning system
developed for the improvement of the recognition of the
Croatian prosody. Learning strategy includes an interactive
course of prosody with progressive exercises and
consistent feedback.
Also, the aim is to make learners aware of prosody in
general (lexical stress, rhythm and intonation) and Croatian
prosody in particular.
A database of words uttered by native speaker of Croatian
serves as a support for the learning and reference for the
correction of learner's productions.
Words in the database are given both in the written and the
spoken form making the dictionary.
We address word-level stress detection of Croatian, where
stressed syllables are characterized by not only power
level, but also pitch, duration and vowel quality.
General stress assignment and stress realization rules in the
standard language are given in the Table1.
Beside these general rules, there are more specific rules,
such as the rule describing that the falling lexical stress can
be carried over to a preceding word: ne + znȁm = nè_znam
(I don’t know). In the standard language this happens when
ne is added to a verb form, and in some preposition +
object phrases: sȁ_mnōm (with me), sȁ_sobom (with
oneself), ù_grad (in the town).
Also, verbs which are derived by adding prefix to the
infinitive verb keep the lexical stress unchanged if the verb
they are derived from has the rising stress. On the other
hand, verbs which are derived by adding prefix to the
infinitive verb that has the falling lexical stress get the
short rising stress on their prefix.
Even more, there are rules for adjectives where twosyllable comparative form needs to have the short falling
stress, while in the polysyllabic comparative stress usually
falls on the third syllable, counting from the end of the
word.
The superlative of the two-syllable comparative always has
the long falling stress on the prefix naj, while the
superlative of the polysyllabic comparative may also
inherit the stress of the comparative, besides the
superlative stress, etc.
All of the above listed rules for stressed syllables are built
in the system.
B. Phase 2.
The exercises were conceived as true learning processes
rather than testing procedures. Up to this point the
following features were incorporated: the system analyzes
the learner's response at every stage giving the consistent
feedback, that is based on the prediction of the most
probable deviations. The system detects the deviations by
comparison between the answer of a learner and a target.
The learner is not placed in the somewhat demotivating
position of being given a limited number of attempts
before having to proceed to the next question, because of
the possibility to choose at any stage whether, either to
give up if his solution was wrong or to have as many
further tries as he wishes. He can choose between
receiving the immediate feedback on completion of each
question and receiving the complete statistics after
answering the each group of questions. The program offers
explanations if learner gives the wrong answer. In standard
tests, written in paper form, learners are not offered any
feedback until the whole exercise has been completed. This
seems to be one of the major disadvantages in the learning
process.
Table1.
General stress assignment and stress realization rules in Croatian
language
STRESS RULES IN THE CROATIAN LANGUAGE
Monosyllabic words may have only a falling stress
Falling stress may occur only on the first syllable
Two-syllable and polysyllabic words may have all 4
stresses on the first syllable
Two-syllable words have stress on the first syllable; words
of three or more syllables may have stress on any syllable
except the last
Stress can never occur on the last syllable of polysyllabic
words
Syllables which are not first nor last (so called inner
syllables) may have only a risinig stress
Although correction is suggested at every stage, it does not
count towards the end result. Each question in the testing
part of the system has a button startng the sound of the
word that user is then supposed to write in the input text
field. This is a kind of optional dictation used because the
different users actually pronounce the words depending on
their dialect background. Yet, if the learner finds the
listening part distractive, he does not have to use the sound
at all. Nevertheless, we think that the listening module
should be interpreted as the extension of the system that
offers possibility of teaching and training the skills of
listening Croatian stressed words as well. At the end of the
each group of questions, the screen displ-ays a score count
of right answers. The program starts with the initial quiz
for testing the basic level of stress knowledge, i.e. it simply
tests the knowledge of recognizing lexical stress and
assigning proper stress mark to the monosyllabic words.
Based on the results obtained, each learner continues
following his own path. If all the questions in the initial
quiz are solved correctly, one can proceede to the second,
somewhat more difficult level. On the contrary, if learner
knows nothing about the stress in Croatian, the system will
take him to the learning module for beginners.
This is the place where two different learning approaches
take place. The deductive learning approach is integrated
in the module consisting of some short introductory notes
on different kinds of lexical stress in Croatian together
with the pronunciation and followed by the main rules for
the monosyllabic words and some examples. The system
continues with a new group of questions in the second
level, to which the learner responds at the keyboard and the
learning process continues. The module built on inductive
learning approach consists of words together with their
pronunciation. Words are quite similar to those contained
in the initial test, but yet organized in groups where the
similarity between the members of the group is high as
well as the dissimilarity between two groups.
Learners are led to carry out conclusions by themselves,
which are actually written rules explicitly given to those
who are following the deductive learning module. The
system proceeds with the second level, using the same
group of questions as the deductive module. On
completion of the second quiz, the learning process is
again inductive. In this way, both groups of learners solve
the same questions on each level, but the transition
between levels is specific for each module.
In the deductive learning approach, explicit statements and
examples are consciously learnt and presented in a
systematically organized way. Statements are given in the
form of rules and learners have to memorize those rules.
Examples are used to explain to learners the theoretical
points and to assign mechanical tasks. Besides, the error
correction is also considered as quite relevant. The samplebased learning approach implies working with the stress
system in an inductive way. Thus, learners work out rules
from data, form hypotheses and test them.
B. Phase 2.
The final test is solved by both groups at the end of the
seventh level and the statistics is written to a database. The
way the statistics is collected is explained in the Fig1.
Hence, the system tracks cumulative results from a
sequence of interactions and passes them along to the web
server. This is performed in a cycle where Flash form
collects and sends data from the user to the database via an
ASP Page that takes the data sent from the Flash interface
and stores it in the database without any change. Finally,
Microsoft Access 2000 database is used to store our data.
The database offers teachers and instructors two kinds of
statistics; the first one presents different groups of the
questions together with the number of correct answers,
while the second offers an overall summary of the results
that the group of learners achieved as a whole.
Statistic results allow teachers and instructors to determine
the aspects of the language stress system that learners have
found the most difficult or those they have not understood
correctly.
IV. DISCUSSION AND EVALUATION
The system was tested preliminary in the laboratory on
two (unfortunately unequal) groups of students, under the
same conditions. The students were all second and third
year students of the Faculty of Philosophy, University of
Zagreb. Some of them had the solid linguistic background,
but the majority of them had little or no knowledge on
lexical stress. In the beginning, we got the impression that
they accepted the task of being tested on using the lexical
stress and learning the lexical stress rules quite toilsome.
Nevertheless, they all made it to the final test.
The final test which followed the deductive learning
approach resulted with the following statistics.
Less than 50 % of the final test solved 22 students. 22% of
them achieved the same result as in the exercises in the
phase 2 (in other words, they learned nothing), 10% of the
students improved their knowledge, while 68% achieved
worse results than in the phase 2.
Around 50% of the final test solved only 5 students, but
out of that number 40% improved their knowledge, while
60% achieved worse results than in the phase 2, and
nobody achieved the same results as in the phase 2.
Around 75% of the final test solved 8 students. 25% of
them achieved the same result as in the phase 2, 25%
improved their knowledge, while 50% achieved worse
results than in the phase 2.
More than 80% of the final test solved 21 student and 52%
of them achieved the same result as in the phase 2, 48%
improved their knowledge, and nobody achieved worse
results than in the first part of the exercise.
On the other hand, the final test which followed the
sample-based learning approach shows the following
statistics.
Less than 50% of the final test solved 22 students, the
same number as in the deductive learning approach. Out of
that number, 31% achieved the same result as in phase 2
(in other words, they learned nothing), 19% of the students
improved their knowledge, while 50% achieved worse
results than in the phase 2.
Around 50% of the final test solved only 2 students, but
they both improved their knowledge, comparing to the
phase 2.
Around 75% of the final test solved 3 students, where 2 of
them achieved the same result as in the phase 2, while only
one achieved worse results. Nobody improved his / her
knowledge.
More than 80% of the final test solved 3 students again.
This time 2 of them achieved the same result as in the
phase 2, one improved his knowledge, and nobody
achieved worse results than in the phase 2.
Table2.
Comparison between deductive and inductive learning approach
regarding the number of students that solved the test and the
percentage of the final test success
Fig. 1. Representation of the FlashMX-server-database
communication
Final test results
< 50%
around 50%
around 75%
> 75%
DL approach
22 students
5 students
8 students
21 students
Total: 56 students
IL approach
22 students
2 students
3 students
3 students
Total: 30 students
Table3.
Comparison between DL and IL approach for students that
achieved < 50% in the final test regarding their previous results
DL
approach
IL
approach
students that solved < 50% of the final test
for 22% of the for 10% of the for 68% of the
students results students results students results
are equal to are better than are worse than
previous
previous results previous results
results
for 31% of the for 19% of the for 50% of the
students results students results students results
are equal to are better than are worse than
previous
previous results previous results
results
Table4.
Comparison between DL and IL approach for students that
achieved 50% in the final test regarding their previous results
DL
approach
IL
approach
students that solved 50% of the final test
for 0% of the for 40% of the for 60% of the
students results students results students results
are equal to are better than are worse than
previous
previous results previous results
results
for 0% of the for 100% of the for 0% of the
students results students results students results
are equal to are better than are worse than
previous
previous results previous results
results
Table5.
Comparison between DL and IL approach for students that
achieved 75% in the final test regarding their previous results
DL
approach
IL
approach
students that solved around 75% of the final test
for 25% of the for 25% of the for 50% of the
students results students results students results
are equal to are better than are worse than
previous
previous results previous results
results
for 75% of the for 0% of the for 25% of the
students results students results students results
are equal to are better than are worse than
previous
previous results previous results
results
Table6.
Comparison between deductive and inductive approach for
students that achieved more than 80% in the final test regarding
their previous results
DL
approach
IL
approach
students that solved more than 80% of the final test
for 52% of the for 48% of the for 0% of the
students results students results students results
are equal to are better than are worse than
previous
previous results previous results
results
for 75% of the for 25% of the for 0% of the
students results students results students results
are equal to are better than are worse than
previous
previous results previous results
results
As one can see from the given statistics, these preliminary
results are hard to compare because the two groups are
unfortunately not of the same size. We consider that as an
obstacle in finding general conclusions. But, there are
some issues which are worth of emphasizing.
Most of the students who had no knowledge of lexical
stress got confused in the final test, after passing all seven
levels.
But, some of them still learned something and inductive
learning approach proved to be better at this stage. Also, if
they had some previous knowledge of the lexical stress,
they improved it following the inductive learning approach
again, but this time they got less confused at the final test.
On the other hand, students that had some linguistic
background never got confused, no matter which approach
they followed, but the deductive learning approach proved
to be more efficient for them.
Therefore, we could say that only after the preliminary
testing results CAL-CROLESS is proved to be a good tool
for students with some linguistic background. Also,
deductive learning approach seems to be more suitable for
them. On the contrary, sample-based approach appears to
be more adaptive to students with no or little knowledge of
the field, but this conclusion needs some more
investigation.
The fact we noticed during the testing is that students start
to feel weariness somewhere in the beginning of the final
exam. We suggest therefore the introducing of a short
break after the last level of the learning process, so that
students can access the final test only after the break and
not immediately after the learning process.
Overall impression was that students found the listening of
the words very helpful and also enjoyed this kind of
interaction. Furthermore, they used the “check answer”
option a lot, although it increased the time they needed to
finish the whole test and regardless of the fact that they
will be introduced with the results on the end of each set of
questions.
In spite of the fact that the task to learn the lexical stress
was quite toilsome, nobody complained at the end of the
session and that proves that CAL-CROLESS accomplished
at least one of its tasks.
V. CONCLUSION AND FURTHER RESEARCH
Multimedia computing, the Internet, and the World Wide
Web have provided an incredible boost of Computer
Assisted Language Learning applications.
The benefits of adding a computer component to language
learning are many, including the multimodal practice with
feedback, individualization in a large class, small group
work on projects, either collaboratively or competitively,
the fun factor, etc. We found that real-life skill-building in
computer use and variety in the learning styles used made
the CAL-CROLESS very attractive to our students.
One of the advantages of CAL-CROLESS is its sensitivity
to the learner’s level of proficiency. It allows learners to
assume mastery of their own learning experience.
Another one of its advantages is that it gives a new role to
language stress teaching materials. Teaching materials in
the written textbook form are usually passive, but in CAL-
CROLESS, because of the interactivness, materials adapt
themselves to the requirements of the individual student.
REFERENCES
The computer skills of learners are not important for
the success of the learning because the interface is very
simple and yet very motivating so that even learners with
little or no knowledge of computers can easily go through
the learning process. Regarding the technical issues we did
not face any problems with different platforms or computer
screen resolutions because we used Macromedia FlashMX
editor and made interface that loads quickly and looks the
same on different platforms.
Further technical development would include the option
for the learner to request a clue while solving the each test.
Also, at the end of each exercise system would display not
only the score, but also the variation of the exercise with
the learner’s answers, both true and false. The result
counter could be set to be much more precise, it could
count second answers but weight them less than the first
attempts, etc. Furthermore, we plan to work on the
development of the CAL-CROLESS which will bring
some new insights regarding the dialectal background of
the user. Our system can easily track the typical mistakes
users make while solving the tests and therefore could be
extended quite successfully to help users to correct these
errors that come from their dialectal background.
Finally, our plan is to develop the whole computer-assisted
Croatian orthography learning system based on the skills
and techniques we learned, problems we solved and results
we obtained building the computer-assisted learning
application for the Croatian language stress system.
[1] Babić, S. “Tvorba riječi u hrvatskom književnom
jeziku.” Nacrt za gramatiku. JAZU, Zagreb, 1986.
[2] Barić - Lončarić - Malić - Pavešić - Peti - Zečević Znika. “Hrvatska gramatika”. II. promijenjeno izdanje.
Školska knjiga, Zagreb, 1997.
[3] Garde, P. “Naglasak.“ Školska knjiga, Zagreb, 1993.
[4] Jelaska, Z. “Fonološki opisi hrvatskoga jezika; Glasovi,
slogovi, naglasci.“ Hrvatska sveučilišna naklada, Zagreb,
2004.
[5] Katičić, R. “Načela standardnosti hrvatskoga jezika. “
Jezik 43 (5), 1996, 175-182.
[6] Mildner, V. “Perceptual acquisition of the long-hort
distinction in the falling accents of standard Croatian.“
Language and Spech, 37 (2), 1994, 163-170.
[7] Moguš, M. “Fonološki razvoj hrvatskog jezika“.
Matica hrvatska, Zagreb, 1971.
[9] Škarić, I. “Razlikovna prozodija.“ Jezik 48 (1), 2001,
11-19.
[10] Šonje, J. (ur.) “Rječnik hrvatskoga jezika.”
Leksikografski zavod Miroslav Krleža i Školska knjiga,
Zagreb, 2000.
[11] Chapelle, C. and Jamieson, J. “Research Trends in
Computer Assisted Language Learning“. In Pennington,
Martha C. Teaching Language with Computers. La Jolla:
Athelstan, 1989.