One of the most important findings from second language acquisition (SLA) research using corpora to investigate formulaicity is that formulaic language takes a long time to acquire. Three major lines of investigation with respect to formulaic language in learner corpora will be discussed in this section: the extent to which Second Language (L2) learners acquire targetlike formulaicity, the role of cross-linguistic influence, and L2-specific formulaicity. Language learning theories have also increasingly emphasized the role of prefabricated or formulaic language. Both first language and SLA scholars are interested in whether language learning is rule-based or whether language is acquired through chunks. The results support the view that formulaic language is a good indicator of second language proficiency, especially at advanced and very advanced proficiency levels. One key characteristic of phraseological studies is that they usually rely on manual analysis of linguistic characteristics to define and identify different types of formulaic sequences.