Two types of grammatical knowledge

This post is primarily an extract from Chapter 6 of The Language Teacher Toolkit (2nd ed., Smith and Conti, 2023). To put it in context, I sometimes wonder to what extent language teachers are aware of the issue of 'types of knowledge' and how fundamental it is to our understanding of pedagogy. The extract beneath examines the issue. The extract is in three parts: the two types of grammar knowledge, the 'interface' issue (this is a biggie) and thirdly, does grammar teaching actually help? To put the issue succinctly: what type of knowledge are we imparting when explaining and practising grammar and this type of knowledge become useful in actual communication?

I have not not listed the references in this post. They can be found in the bibliography of our book.

1. Two types of grammatical knowledge

Hossain Nassaji (2017) reminds us of a long-standing controversy in the field. Does learning develop primarily through explicit teaching and conscious manipulation of structures, or merely through unconscious processes when people are exposed to meaningful input (known as implicit learning)? Psychologist Nick Ellis (2012) points out that implicit and explicit learning are functions of separate memory systems in the brain. Scans show that explicit learning is supported by neural networks located in the prefrontal cortex, whereas implicit learning involves other areas of the brain, the perceptual and motor cortex. So physical evidence suggests a clear distinction between explicit (conscious) and implicit (unconscious) learning.

Explicit learning leads to explicit knowledge, often called declarative knowledge, i.e. ‘being able to explain the rules’. This in itself is not much use when it comes to speaking and comprehending in real time. Implicit knowledge is taken to occur based on extensive meaning-focused input, acquired without awareness and stored implicitly (speaking the language without being able to explain the rules).

Some researchers, (such as Ullman, 2006) believe that grammar and vocabulary are stored differently in the brain. They suggest that vocabulary is stored as declarative memory, whereas grammar is stored as implicit or procedural memory. This may explain why using grammar accurately is harder for students than recalling vocabulary. In other words, you might say that the system (grammar) is harder to acquire than its components (vocabulary). Ellis and Shintani (2013) sum up the differences between implicit and explicit knowledge (see Table 6.1).

 

Implicit and explicit knowledge (adapted from Ellis and Shintani, 2013).

 

Characteristics	Implicit knowledge	Explicit knowledge
Awareness	No conscious awareness of rules but knows what ‘sounds right’	Consciously aware and can explain rules
Type of knowledge	Procedural, i.e. available for automatic processing	Declarative – facts about the L2 only available through controlled processing
Systematicity	Variable but systematic	Often inconsistent since students may have a partial understanding of the grammatical feature
Use of L2 knowledge	Evident when used for communication	Used to monitor production; used when students lack implicit knowledge
Self-report	Internalised constructions which may not be easily reported	Can be reported using metalanguage (grammar terminology)
Learnability	May be age limits on ability to acquire grammar implicitly	Learnable at any age, but older learners have more world knowledge

It is worth pointing out immediately, that explicit knowledge is much easier to acquire than implicit. It is all too easy to imagine that when students have good explicit knowledge, they can convert this to implicit. In fact it is not easy, as we shall see in the next section.

2. The interface question 

What is the relationship between these two types of knowledge? In particular, can explicit knowledge become implicit? Traditionally there have been three views about this which involve what is called the interface between explicit and implicit knowledge.

The no-interface position (e.g Krashen, 1982) holds that explicitly, consciously learned language cannot become implicit. Instruction makes no difference - all you need is meaningful exposure to language. The strong interface position (e.g. DeKeyser, 1997) holds that implicit knowledge can result from proceduralisation of explicit knowledge, i.e. through explanation and practising the skills you can become proficient. In this view, students can use explicit knowledge to consciously construct utterances in working memory. The weak interface position argues that explicit knowledge facilitates the acquisition of implicit knowledge.

Critics of the strong and weak interface position (e.g. Lichtman and VanPatten, 2021) argue that no mechanism has been described to explain how explicit knowledge can become implicit. Brain scanning shows the two types of learning happen in different brain areas. Nick Ellis (2005) has suggested, however, that explicit and implicit knowledge work in cooperation, not separately. Unlike the strong interface and the non-interface positions, the weak interface refers to noticing and ‘noticing the gap’. Noticing refers to the conscious cognitive effort of detecting and paying attention to language features as a necessity for language acquisition while noticing the gap refers to when learners notice a mismatch between what they say/know and what native speakers say (Schmidt, 1990). This is known as Schmidt’s Noticing Hypothesis. Scholars do not agree about the extent to which ‘noticing’ is needed for structures to be acquired (i.e. internalised for spontaneous use). Indeed, by 2010 Schmidt had softened his view on this (Schmidt, 2010).

A final point to note is that DeKeyser’s (1997) strong interface position comes with some caveats. He argues that you need a certain set of circumstances for explicit knowledge to be successfully automatised, e.g. learners need to be adult and have a certain level of aptitude. In addition, he argues that there is a difference between automatised explicit knowledge and implicit knowledge. Both involve rapid access to linguistic knowledge, but explicit knowledge involves consciousness about linguistic features, whereas using implicit knowledge requires no awareness (Suzuki and DeKeyser, 2017). In reality, it is not always clear to language learners whether they are speaking based on rules they know or feel (McLaughlin, 1978). For most teachers this distinction may not seem very important, as long as students can use the L2 successfully for their purposes or for an examination.

3. Does teaching grammar help?

You might be surprised to even be asked that question, but some scholars in the field, e.g. Stephen Krashen and John Truscott, argue that grammar teaching makes little or no difference to developing students’ proficiency. Their reasoning goes back to the interface issue referred to above. They argue there is no evidence that declarative knowledge of grammar can become procedural skill. On the other hand, Michael Long (1983) looked at 12 studies comparing learning through exposure with ‘instructional’ learning and concluded that overall instruction made a positive difference at all levels with both children and adults. Rod Ellis (1990, 1994) and Larsen-Freeman and Long (1991) also found that instruction helped with the rate and ultimate level of acquisition. More recent studies have reached the same conclusion (Norris and Ortega, 2000; Spada and Tomita, 2010; Goo et al., 2015).

Overall, the empirical evidence favours instruction, but what type of instruction? It has been argued that the studies mentioned here only really measured improvement in the accuracy of certain grammatical forms. But the Spada and Tomita (2010) study found that grammatical improvement was measurable even in spontaneous speech. Kang, Sok & Han (2018), having analysed 54 studies from 1980 up to 2015 found that instruction was useful, especially for beginners, but that implicit instruction had a longer-lasting effect. However, let us be clear – explicit grammar teaching probably helps our students less than you think. Using the language is much more important.

Pawlak (2021) examined the evidence about whether grammar is better acquired through explicit instruction or by picking it up implicitly through input and usage. He reminds us that the rules and patterns of pedagogical grammars (the type we find in grammar manuals and textbooks) have little to do with the mental reality of learners' interlanguage (the unconscious mental model of grammar that learners are developing as they learn). He notes that just because students have explicit knowledge of pedagogical grammar, it does not mean they can apply it in real time. Nevertheless, he suggests, following DeKeyser (2012), that students who have relatively little contact time with the L2 can rely on ‘automatised explicit knowledge’ to get them by since they do not have time to build a large foundation of implicit knowledge. (In practice, most teachers would not be too worried whether students are using implicit knowledge or automatised explicit knowledge!) His conclusion is:

...the predominant goal of GI (grammar instruction) is to help learners develop implicit knowledge, or much more realistically in many contexts, automatise the explicit knowledge they have at their disposal. (Pawlak, 2021).

 

He also cites Nassaji and Fotos (2011) who stated    "... teachers should be eclectic in their pedagogical approach."