1. Introduction

In recent years, with the increasing emphasis on languages and the growing demand in work and life, the second language acquisition of English has gradually developed towards younger age groups and more diverse groups. This trend leads to different difficulties faced by learners from various mother tongue backgrounds due to the features of their mother tongue backgrounds [1]. In second language acquisition, articles are considered to be one of the most complex linguistic phenomena.

As a functional word class, articles carry rich semantic information such as definite and indefinite reference and play a qualifying or non-qualifying role for nouns in context, thus giving nouns a more precise referential function [2]. For example, the definite article 'the' is used to refer to a known object in particular, whereas the indefinite article 'a' is used to refer to an unspecified object in general [3]. Lado points out that this distinction between specific reference and general reference is one of the core elements of the article system [3]. In English second language acquisition, articles are not only a part of grammatical structure, but also have a significant impact in the systematicity and integrity of second language learning and expression due to their characteristics [3]. However, since the article system is not a feature common to all languages, differences in native language background play a key role in the acquisition. The phenomenon of L1 transfer is particularly evident in the acquisition. Lado states that if learners have a similar article system in their native language, they are more likely to benefit from positive transfer when using articles [3]. On the contrary, learners without an article system in their language are more likely to experience negative transfer, resulting in errors such as omission, misuse or inappropriate use [3]. This transfer phenomenon has a direct impact on learning outcomes. Research carried out by Lado shows that the differences between the L2 learner's first language and the target language have bearing on the quality and effectiveness of the L2 learner's acquisition [3]. Understanding these variations is of great importance for enhancing article teaching methods and helping learners develop their learning quality and efficiency. This paper provides a basis for the future personalization of the article teaching and the optimization of teaching methods. It also provides a basis for the personalization of article teaching and the optimization in the future.

2. Review of related theories

2.1. Contrastive Analysis Hypothesis

In second language acquisition, the contrastive analysis hypothesis has been used as a basic theory that explains how the similarities and differences between the mother tongue and the target language affect the learning process. When the mother tongue and the target language have similarities in a certain language phenomenon, learners are more likely to make some positive transfer, thus reducing errors in the learning process [3]. In contrast, the absence of such phenomena or structures in the mother tongue increases the risk of negative transfer and causes the difficulty of second language acquisition [3]. Therefore, the contrastive analysis hypothesis is often used to explain why L2 learners from different mother tongue backgrounds have diverse difficulties and biases in mastering English articles. For example, negative transfer is more common among learners without articles in their mother tongue, and these learners are prone to make frequent mistakes in the selection and use of articles.

2.2. Three basic theories about articles

English articles are one of the most frequently used functional words in English, and they are grammar knowledge that English learners will come into contact with at an early stage [4]. It carries semantic information such as expressing definite and general meanings [4]. However, many languages do not have similar article systems, which leads to more difficulties for those learners in learning. The relationship between English article acquisition and mother tongue background has been studied for a long time. The theoretical formation of its acquisition process mainly went through three stages: Chomsky's Universal Grammar Theory, Ionin's article semantic fluctuation hypothesis, and interlanguage syntactic impairment theory.

2.2.1. Chomsky's universal grammar theory and Ionin's semantic fluctuation hypothesis

Chomsky's universal grammar theory explores the mechanism by which different mother tongue backgrounds affect learners' language learning and use. The theory holds that all languages share a basic set of grammatical conditions, but different languages form unique grammar systems through different parameter settings [5]. Ionin, Ko and Wexler put forward the"Article semantic fluctuation hypothesis" in 2004, which further discusses the instability in article acquisition on the basis of the universal grammar theory [6]. In 2004, Ionin and Wexler's study of the semantic fluctuation hypothesis specifically focuses on learners who lack article systems in their native language, such as Korean and Russian native speakers, and tests their choice of articles in particular contexts through forced choice tasks [6]. It is found that this variety of learners show volatility in article selection, which means they can not use the correct articles steadily in similar contexts [6]. Ionin states that this fluctuation results from the learners' uncertainty in the input environment [6]. They try to use the correct articles by adjusting the article parameters, but it is difficult to form fixed rules [6]. This phenomenon is consistent with the parameter-setting theory of universal grammar theory and provides a powerful explanation for the difficulties in article acquisition as well [6].

2.2.2. The feature deficit hypothesis

In 1997, Hawkins and Chan proposed the feature-deficit hypothesis based on Chomsky's universal grammar theory. This hypothesis explains the learning difficulties experienced by adult second language learners with certain functional grammatical features, such as tense, articles, and auxiliary verbs [7]. A study carried out by Hawkins and Chan tested the performance of Chinese-native second language learners in learning articles and found that Chinese learners were still unable to use articles correctly in the appropriate context after long-term input and learning [7]. Researchers believe that it is due to the absence of article system in Chinese, so learners are unable to fully and successfully activate the function of articles in universal grammatical rules [7]. In subsequent empirical studies, findings by White and Lardiere also support this hypothesis. White's study examined the difficulties encountered by learners whose native languages do not have an article system, such as native speakers of Chinese and Russian, and found that they had difficulties in acquiring the articles only through input [8]. Lardiere tracked the article acquisition of second language learners and found that even with a large amount of input, they were unable to fully master the use of articles [9]. Lardiere's research also points to the irreversibility of these functional characteristics in second language acquisition [9]. Based on the functional deficit hypothesis, studies argue that learners with a non-article system in their mother tongue encounter great difficulties in learning.

2.2.3. Theory of syntactic damage in interlanguage

Beck proposed the theory of syntactic damage in mediated language in 1998 which is a language system different from the native language and the target language [10]. This system is produced by learners when they are in the process of second language acquisition [11]. The theory mainly explains the reasons for syntactic errors made by second language learners in acquisition which is due to the damage of mediated language [11]. It would lead to the learners' inablility to fully master a particular syntax, especially those involving functional words or complex grammatical structures [10]. In 2014, Paramasivam conducted a study with non-article native speakers (Malay and Mithaiyar) to analyze the group's error patterns in using articles [12]. The study found that errors occurring in the use of articles fall into the following three main types: omission of articles, overuse of articles, and confusion of articles [12]. It is due to the lack of a similar article system in the native language which makes learners encounter several obstacles in the use of articles [12]. By researching difficulties that arise in the acquisition of English articles by learners with no article system in their native language, this study confirms that native language transfer and syntactic impairment in the theory of syntactic impairment in mediated language do have an impact on second language acquisition [12]. This hypothesis also elaborates the reasons why grammatical syntactic features such as articles are great barriers in second language acquisition.

3. Review of relevant empirical studies

3.1. Empirical studies of learners without article systems in their native language context

Learners often face great difficulties in acquiring English articles if there is no article system in their native language. The research conducted by Crosthwaite in 2016 shows that error types in article using are closely related to the structure and characteristics of their respective native languages made by learners from different backgrounds [13]. In addition, native language transfer also plays a key role in the acquisition of articles, significantly affecting learners' performance [13].

3.1.1. Problems by native Japanese speakers in article acquisition

The main difficulty for native Japanese speakers in acquiring English articles is due to the differences in grammatical features between two languages. Japanese does not have a specific article system, and the functions of specific reference and general reference are mainly realized through the case particles 'は' 'が', and the demonstrative pronouns 'この', 'その', 'あの', etc [14]. This structure is fundamentally different from English articles [14]. Therefore, native Japanese speakers have difficulty in understanding the functions of specific reference and general reference performed by the articles learning [14].

In 2002, Goto Butler carried out a study with a combination of quantitative and qualitative methods [14]. The research group consisted of 80 local Japanese university students and 20 Japanese university students studying in the United States [14]. The 80 Japanese university students were divided equally into four groups according to their English proficiency [14]. They were distributed questionnaires on article selection in the first part, while a structured interview was conducted in the second part [14]. These record specific difficulties that native Japanese speakers encountered in acquiring articles, and explore the causes of difficulties [14]. The study found that the more proficient native Japanese speakers were with English articles, the more target-like usage they could use, but even the most proficient group still had a significant gap compared to native speakers [14].

In 2002, Goto's study also found that Japanese learners often struggle to distinguish the semantic differences between definite and indefinite articles, resulting in frequent errors in article selection [14]. For example, native Japanese speakers vary in their understanding of the specific meaning and contextual applicability of articles, which is manifested in the confusion of definite and indefinite articles [14].

Native Japanese speakers also face the problem of missing articles in English learning. In 2003, Kanno's study found that since there is no similar use of articles in Japanese, Japanese speakers tend to neglect articles during the learning process, especially when expressing specific or general references, and they usually only use nouns [15]. Kanno's research shows that even native Japanese speakers with a high level of English proficiency still miss articles [15].

In 2018, Watanabe found that expressions of specification often rely on the context or the use of demonstratives rather than articles in Japanese, making it difficult for native Japanese speakers to determine their role in reference when learning articles [16]. For example, when discussing known information, they may not get accustomed to using the definite article 'the' to express the known nature of the information for the listener or reader, but rather rely on the context. This tendency also leads to misuse or bias in article acquiring [16].

In a study in 2022, Takahashi found that native Japanese speakers are unable to achieve proper semantic fluctuation regulation: native Japanese speakers have difficulties in choosing the appropriate article when using articles, which is consistent with the article semantic fluctuation hypothesis [17]. These learners show 'fluctuations' in semantics, i.e. they found it hard to make stable judgments about the rules for using articles in specific contexts, which can further lead to misuse of articles [17].

3.1.2. Problems by native Chinese speakers in article acquisition

Chinese, as a non-article language, also occupies an extremely important position. Chan conducted a research on the acquisition of articles among Chinese people including school students and adult English learners [18]. This study analyzed the English writing of Chinese native and collected and organized the common types of article errors by subjects: omissions, mistakes, and inappropriate use [18]. Research questionnaires are distributed to the English teachers to understand students' article knowledge and acquisition based on their teaching experience [18]. Structured and semi-structured interviews were also conducted with typical subjects to analyze in depth the reasons for their article using and to summarize specific problems [18]. The study carried out by Chan found and confirmed that the grammatical structure of Chinese has a significant impact on second language learners' acquisition of articles [18]. For example, in English, learners write "dog" directly instead of "a dog" with an indefinite article [18]. The reason is that the Chinese do not require an article to express the meaning of specificity or non-specificity [18]. Xu Qihao's research also shows that the use of articles by Chinese often fluctuates between definite and indefinite articles [19][20]. In summary, native Chinese speakers meet considerable difficulties in acquiring English articles due to the lack of an article system in their native language background.

3.1.3. Other problems for native speakers of languages without articles

Native speakers of other languages without article systems also encounter great challenges in article acquisition for similar reasons: there is no structure of article systems in the mother tongue, so the article can not be transferred to the target language. For that reason, learners can not understand what the information is really about, or they probably misunderstand the context information and the article use [21][22]. It leads to omitting and misusing of the article by learners. For instance, native speakers like Russian, Korean, and Turkish all experienced similar difficulties in article acquisition as description above [1][13][21].

3.2. Empirical research on the presence of articles in the native language context

Second language learners with article systems in their native language background will be affected by positive transfer, they will still encounter challenges in acquiring articles. However, due to differences in specific usage rules and contexts, they will still differ. In 1997, Hawkins and Chan's study mentioned that French and English have similarities in their article systems, so learners can exhibit positive transfer in learning, and they will correctly understand and master the semantic information carried by definite and indefinite articles [7]. Due to differences in detail, for example, in French, an article is usually required in front of uncountable nouns, and a partial article is used in general reference, while it is not required in English [7]. In this case, French native speakers are prone to errors in the use of English articles, such as the extensive use of articles before indefinite articles and errors in the judgment of generality and specificity [7].

In Spanish, although native speakers can benefit from positive transfer in the acquisition of articles with the similar article systems, there are still differences in detail [6]. In expressions referring to uncountable nouns, articles are usually added in Spanish. For instance, to express 'I want bread', the Spanish expression is 'Quiero el pan', and 'el' is the definite article [6]. If it wants to refer to uncountable nouns in particular, Spanish also uses the definite article 'el' or 'la', like 'El agua es importante' (The water is important) [6]. This difference leads to acquisition problems, such as the overuse or misuse of articles by native Spanish speakers [6]. Snape & García-Mayo further analyzed the acquisition of Spanish native speakers and found that although native speakers can better understand the article system in English based on positive transfer from their native language, there are still problems with misuse or misapplication in more complex expressions such as colloquialisms or uncountable nouns [20].

German is another language with articles, but the gender, number, and case matching requirements in its article system could lead to errors in English article uses by native German speakers. For example, native German speakers will lead to mistakes in specific contexts by introducing the gender and case changes of German into the use of English articles, especially when the article is paired with a subject or object noun [23][24]. In studies by Giuliano and Ionin, native Italian speakers also had similar problems: the use of articles in Italian is more frequent, which also leads to article overuse in English [6][25].

4. Conclusion

This paper collates and analyses the performance of second language learners in acquiring English articles and the different difficulties they face from different mother tongue backgrounds. In this review, learners are divided into two directions: learners with an article system in their native language and learners without. Previous research has shown that mother tongue background has a significant impact on article acquisition, and learners whose mother tongue does not have an article system face particularly significant difficulties. When there is an article system in native languages speakers, they have to overcome the negative transfer caused by their native language, which results in the misuse of English articles, especially in complex sentence structures and idiomatic expressions. Even if there is an article system in the native language, further in-depth systematic learning is still required.

This review just covers a limited number of languages and the research of article use is not thorough enough in real communication scenarios by learners from different mother tongue backgrounds. Factors such as the age, mood and learning motivation of the second language learners are not included. In future research, it is hoped that the above will be addressed in depth and comprehensively.