This research paper aims at illuminating some of the effects that multilingualism and linguistic diversity might have at the societal level with regard to various attributes of social life. In doing so, a thematic review of previous research on the effects of multilingualism is carried out. Particular focus was paid here to a number of areas in which multilingualism can have specific and major effects on social life, e.g. education, economy, as well as employment and language policy. Following attempts to problematize the notion of multilingualism, the article concludes that language-related problems evident in multilingual societies appear to be largely attributable to (language and language education) policies implemented by governments concerned.

Intuitional data elicited by means of grammaticality judgement (GJ) tasks are affected by a diverse number of linguistic and non-linguistic factors including the type of the measurement scales and the response formats used (see Schütze, 1996;Sorace, 1996). The problems associated with the rating scales vary according to the type of the rating scale used -whether absolute or comparative. Such problems pose a serious challenge to linguists to find an alternative rating scale that can overcome these methodological problems and pitfalls. The only way to do so is by using a new rating scale which allows sharp lines to be drawn between the learner's certainty, doubt and lack of knowledge reflected in his or her judgements. The four-point scale in its new format proposed in this article (i.e., clearly correct, clearly incorrect, possibly incorrect and do not know) managed to map the territory between the three possibilities that capture a learner's feelings towards any given sentence. What is unique about this rating scale compared to others commonly used in grammaticality judgments (i.e., Coppetiers, 1987, Schachter andYip, 1990;Schachter, 1990;Gass, 1994) is how it works and how the data obtained by means of this scale can be marked and scored. The purpose of the present article is to introduce this scale and to discuss from a logical point of view the extent to which it can produce reliable and valid data that reflect second language (L2) learner's interlanguage knowledge.

This article introduces the Universal-Grammar-based (UG) theory of language acquisition. It focuses on parameters, both as a theoretical construct and in relation to first-language acquisition (L1A). The null subject parameter is used to illustrate how languages vary and explain how a child's grammar develops into adult grammar over time. The article is structured as follows: the first section outlines crucial ideas that are relevant to language acquisition in generative linguistics, such as the notions of competence, performance, critical period, and language faculty. Section two introduces and discusses the content of language faculty from the perspectives of the Principles and Parameters Theory and the Minimalist Program for Linguistic Theory. This section also briefly describes the contrast among languages in regard to whether or not they allow empty categories in subject position in finite clauses. The third section first discusses how children are hypothesised to acquire their native language (L1). Then, in light of findings from the early null subject phenomenon, this section empirically examines the content of grammars that are developed by children at various developmental stages until they acquire the appropriate value for the null subject parameter. The final section highlights the important role of UG theory to L1A.Keywords: Universal Grammar, first language acquisition, language faculty, critical period, null-subject, the Principles and Parameters Theory, The Minimalist Program International Journal of Linguistics ISSN 1948-5425 2017 www.macrothink.org/ijl 49 UG and Child Language AcquisitionThe field of linguistics has been developing very rapidly. During the last century, several theories have emerged. One which has opened new perspectives in our understanding of both language structure and language acquisition is the theory of Universal Grammar initially proposed by Chomsky in 1957. Chomsky (1975 defines this notion as ''a system of principles, conditions, and rules that are elements or properties of all human languages''. The idea is that these principles, conditions, and rules are found in all languages because they are a property of the human mind. With its ultimate aim of integrating ''grammar, mind and language at every moment' ' (Cook and Newson, 2007, p. 11), the primary goal is to ''understand the mechanisms which underlie the human ability to build mental grammars '' (Hawkins, 2001, p. 1). However, understanding the nature of these internally operating mechanisms ''is inseparable from the problem of how it [language] is acquired' ' (Cook and Newson, 2001, p. 2). (Note 1) Hence, linguists, in order to describe properly such an abstract mental grammatical system need to answer the question: how do children so masterfully acquire the complex knowledge of their native language?Following the idea which regards language ''as a natural phenomenon'' (Lenneberg, 1967, p. vii) which should be studied as an ''organ of the body'' (Chomsky, 2005, p. 133), Chomsky (1957, and much of his ...