Second language acquisition is the attempt to acquire a language while already competent in another. There is a distinction between a child being naturally exposed to two languages and a child or adult learning in a classroom setting. In terms of second language acquisition itself, linguistic structures such as syntax may be harder to grasp after a critical period. People also have less time and motivation to pursue language learning in earnest. In addition, the contrasts between L1 and L2 may aid or hinder acquisition. Generally, the more different L2 is from L1 in some feature, the more difficult it will be to learn.
Initial learning of L2 is good and then declines before the learner becomes more proficient (McLaughlin & Heredia, 1996). This decline is explained by the substitution of less complex internal representations with more complex ones. For example, the learner acquires the use of syntactic rules as opposed to repeating sentences by rote. The traditional method for second language teaching is based on translating from one language into another. On the other hand, direct learning involves learning conversational skills in L2. Some methods prefer speaking and listening over reading and writing. Immersive learning is a technique where all learning is conducted in L2.
In addition to various teaching methods, the characteristics of the individual learner also play a role in second language acquisition. Carroll (1981) identified four sources of variations:
- Phonetic coding ability: the ability to identify new phonemes in L2
- Grammatical sensitivity: the ability to recognise words in terms of their grammatical function
- Rote learning ability: the ability to learn through memorization and recall
- Inductive leaning ability: the ability to infer linguistic rules from the language