A study conducted at Northumbria University, England, has shown that many native English speakers are unable to understand elements of basic grammar.
The project used sample sentences and tested a wide range of adults, including some postgraduate students, asking the participants to identify the meaning of the sentences. Noam Chomsky’s theory of universal grammar assumes that grammar is innate, and everyone has the same core grammar – sort of ‘hardwired’ into the brain, like other skills such as learning to walk. However:
As the test progressed, the two groups performed very differently. A high proportion of those who had left school at 16 began to make mistakes. Some speakers were not able to perform any better than chance, scoring no better than if they had been guessing.
[Researcher Dr Dabrowska] adds: “Our results show that a proportion of people with low educational attainment make errors with understanding the passive, and it appears that this and other important areas of core grammar may not be fully mastered by some speakers, even by adulthood.
“These findings could have a number of implications. “If a significant proportion of the population does not understand passive sentences, then notices and other forms of written information may have to be rewritten and literacy strategies changed.
“What’s more, the existence of substantial individual differences in native language attainment is highly problematic for one of the most widely accepted arguments for an innate universal grammar: the assumed ‘fact’ that all native speakers of a language converge on essentially the same grammar. Our research shows that they don’t.” (Source: Science Daily)
Perhaps this could be part of the reason why some people find picking up the grammar of a new language so difficult?