Second-language Acquisition - Comparisons With First-language Acquisition

Comparisons With First-language Acquisition

People who learn a second language differ from children learning their first language in a number of ways. Perhaps the most striking of these is that very few adult second-language learners reach the same competence as native speakers of that language. Children learning a second language are more likely to achieve native-like fluency than adults, but in general it is very rare for someone speaking a second language to pass completely for a native speaker. When a learner's speech plateaus in this way it is known as fossilization.

In addition, some errors that second-language learners make in their speech originate in their first language. For example, Spanish speakers learning English may say "Is raining" rather than "It is raining", leaving out the subject of the sentence. French speakers learning English, however, do not usually make the same mistake. This is because sentence subjects can be left out in Spanish, but not in French. This influence of the first language on the second is known as language transfer.

Also, when people learn a second language, the way they speak their first language changes in subtle ways. These changes can be with any aspect of language, from pronunciation and syntax to gestures the learner makes and the things they tend to notice. For example, French speakers who spoke English as a second language pronounced the /t/ sound in French differently from monolingual French speakers. This effect of the second language on the first led Vivian Cook to propose the idea of multi-competence, which sees the different languages a person speaks not as separate systems, but as related systems in their mind.