This paper reviews definitions of input from different perspectives, which is then followed by a discussion on influential factors that can affect the process of second language acquisition (SLA) originating from the input itself, the learners’ internal and external sides. Despite researchers’ agreement on the significance of input acknowledging that without input, language acquisition does not occur, there are a great number of definitions of input presented from various viewpoints. | An Giang University Journal of Science – 2017, Vol. 5 (2), 81 – 89 INPUT IN SECOND LANGUAGE ACQUISITION Chi Do Na1 1 An Giang University Information: Received: 19/01/2016 Accepted: 20/03/2016 Published: 06/2017 Keywords: Input, second language acquisition, influential factors, requirement ABSTRACT This paper reviews definitions of input from different perspectives, which is then followed by a discussion on influential factors that can affect the process of second language acquisition (SLA) originating from the input itself, the learners’ internal and external sides. Despite researchers’ agreement on the significance of input acknowledging that without input, language acquisition does not occur, there are a great number of definitions of input presented from various viewpoints. The writer therefore explores how input has been defined extending from the broadest as what is available for acquisition to the narrowest sense which include linguistic features at a higher level beyond learners’ current states of language development. Particularly, input needs to meet certain requirements regarding its accuracy for successful language acquisition. different positions in relation to the role and significance of input (Saleemi, 1989). No matter how differently input is defined, Gass (1997) argues that it is undeniable that input is “the single most important concept of second language acquisition” (). The importance of input is also confirmed by other researchers. For example, VanPatten (2003) extends the research into input by emphasising the critical nature of substantial exposure to the process of language learning. Wode (1981, as cited in Saleemi, 1989) notes the importance of input in SLA, stating “there is no learner on record who learned a language or even part of it without receiving some language input” (). This research supports the point that if learners are not exposed to the target language in the input, they cannot acquire that language. To strengthen
