Interference is a psycho-linguistic concept which is a reality in language learning. Errors in second language learning are partly attributable to interference. Theorists of interference believe that acquisition of the first language usually affects performance in subsequent language acquired.
Interference as a linguistic problem is common in communities where second languages (usually the lingua franca) must be learnt. In other words, interference is a term which refers to a situation whereby two different languages overlap.
In this situation, the linguistic systems of one of the languages is transferred into the other in the process of producing the latter which is the second or target languages.
In interference, one of the two or more languages in use in a speech community is dominant. The features of the dominant language are transferred to the subordinate or target languages at the phonological, lexical, grammatical and discourse levels.
One major cause of interference is interlingua identification. That is a situation whereby the bilingual equates two separate elements of the two languages in contact. interference cases therefore occur when learning and performance in English is impeded by the transfer of speaker's knowledge of his mother tongue or other acquired languages before contact with English.
TYPES OF INTERFERENCE
Two types of interference can be distinguished. The first type is the proactive interference. This is an interference phenomenon that helps in the acquisition of the target or subordinate language. For instance, sounds such as /b/, /d/, /t/, which occur in most Nigerian languages aid the acquisition of similar sounds in English phonology. The other type of interference is the retroactive type. This type retards the process of the acquisition of the target language. For instance, lack of sounds such as the voiced labio-dental /v/ and the voiced dental fricative / / which are present in English but are absent in Yoruba for instance make it difficult for Yoruba English bilingual to acquire the English sounds. Similarly, the lack of long vowels in Yoruba hinders the acquisition of long vowels in English by Yoruba English bilingual. It is difficult at times for these learners to distinguish between such words sit, /sIt/ and seat /si:t/. Also, there are some sounds in English language which the Yoruba Language does not have e.g /z/ its/ sounds. A Yoruba speaker is likely to pronounce Zoo as (Soo) and champion as ( Shampion) because of the /z/ and /t S / sounds.
Interference is either positive or negative transfer of the linguistic knowledge of a language into performance in the other. Negative transfer pertains to difficulties in using the target language which are mainly attributed to mother tongue interference. Positive transfer however implies the ease or facilitation in learning the L 2 resulting from similarities between the L 1 and L 2 .
HYPOTHESES ON INTERFERENCE PHENOMENON
In handling interference concept, contrastive linguists identify three hypotheses: The strong hypothesis; The weak hypothesis and Eckman Markedness Differential Hypothesis.
The strong hypothesis emphasizes that students' linguistic background need to be identified by English teachers. Under the strong hypothesis, English teachers are expected to demonstrate competence in identifying the linguistic background of the learners. On the other hands, the weak hypothesis hinges on assigning tasks to English students for their interference problems to be identified, while Eckman Markedness Differential Hypothesis considers the comparison of the linguistic features of English and students' native languages in terms of linguistic features similarities and differences.
PHONOLOGICAL PROBLEMS OF YORUBA LEARNERS OF ENGLISH.
Phonological problems of Yoruba learns of English is called phonic interference. Phonic interference suggests the transfer of the rules guiding the production of speech sound of a dominant language in a speech community to the sounds system of a subordinate or target language. This can be realized at the phonemic, stress and intonation levels. At the phonemic level, interference is predominant. This is because of the differences between the sound patterns of the mother tongue of Nigerian. English bilingual and the sound patterns of the English language. For instance, the presence of certain consonants and vowels in Nigeria indigenous languages facilitate the acquisition of such similar sounds of the English language. Such sounds include voiced bilabial plosive /b/, voiceless alveolar plosive /t/, /d/ as well as short vowels such as /i/, /u/, and /e/. However, the absence of the English sounds such as short voiceless bilabial plosive /p/, voiceless and voiced labiodentals fricative // and / / and the long vowels /i:/, /u:/ and /:/ , etc, in Yoruba, for instance, makes it difficult for Yoruba English bilingual to acquire such sounds. Thus, some Yoruba- English bilingual will produce pat' as /kpt/, fever' as /fifa/ and think' as /tink/.
At the syllabic level most Nigerian Languages including Yoruba lack consonant clusters e.g Screwdriver /skrdraiv/ would come out this way to the Yoruba speaker su/ku/di/ra/fa/: because in the Yoruba language, a vowel follows a consonant directly.
There are also noticeable interference features at the stress and intonation levels. The fact that most Nigerian languages are tonal while English is stress timed and intonational creates some problems for Nigeria English bilinguals in learning English sounds. Thus a Yoruba - English bilingual stresses every syllable in the utterance he produces in English, e.g. cha'ra'cter instead of character or Ma'ry instead of Mary. At the level of intontion, because all the syllables are stressed, a carry over effect from the dialects of Yoruba language, it becomes difficult to understand what part of an utterance a Yoruba - English bilingual is trying to emphasize.
LEXICO SEMANTIC PROBLEMS OF THE YORUBA LEARNER OF ENGLISH
The lexico - semantic interference is caused by cultural differences between dominant and subordinate language. At this level, the entire culture is involved and because of the involvement of different concepts in different cultural backgrounds, there are areas of conflicts resulting in difficulties.
In Nigeria , it is acceptable to have several wives thereby making it possible to have names for the head wife, young wife, co-wife e.t.c in Nigeria context but not in British context.
In case of lexical interference in contrastive analyses, he takes two different forms. The first form can be traced to linguistic factors while the other form can be traced to cultural factors. Lexical interference identified linguistically are regarded as errors, whereas those identified culturally are not so regarded; moreso when the latter expresses the local colour of socially recognized phenomena.
SYNTACTIC PROBLEMS OF THE YORUBA LEARNER OF ENGLISH
Syntactic problems as factors of interference involve the comparisons of the structure of two languages such as English and Yoruba with the aim of identifying area of difficulties. The syntax of English and Yoruba language have recognize problem areas as the nominal system (such as number, quantifier, pronoun/gender, embedded structures relative pronoun, complements), the verbal system (such as tense/aspect/modal ) and the expression of passive.
DISCOURSE PROBLEMS OF YORUBA LEARNER OF ENGLISH
At the level of discourse there could be interference. This is more pronounced at the level of greeting. For instance, the system of greeting in Yoruba differs considerably from that of English. And a Yoruba English bilingual transfer the system of greeting in Yoruba into English. The system of greetings is also observed via the production of lengthy greeting in place of casual greetings which characterize the English discourse.
GRAMMATICAL PROBLEMS OF YORUBA LEARNER OF ENGLISH
At the grammatical level, there could be interference. Mother tongue obviously affects the learner's understanding of grammatical rules of target language because the two are of different models.
Grammatical interference depends on the level of competence of the bilingual involved. For instance, the level of competence of primary school pupils may be different from that of secondary school pupils.
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BY: ONIKE RAHAMAN