“How many hours of standard, educated English will a native speaker have been exposed to by, say, age 15. Whatever number you pick, if you expect an EFL student to use the language at an equivalent level without error correction or grammar instruction, you’ll have to find a way to get that student an equal amount of exposure. Get out your calculators, folks at ten hours exposure to English per week (a generous amount for a Chinese EFL student), the number of YEARS required is going to be well into the triple digits. Your students great-great-grandchildren will all be retired before your students will have acquired the ability to write like a 15-year-old.”
Krashen’s theories on the “acquisition” of language facilitated through “comprehensible input” at a level of “i+1” is not just something that sounds like a good idea until someone pulls out a calculator and does the math. Although the subject is widely debated, there is a lot of evidence that it works and you can read research after research on Krashen’s website at: http://www.sdkrashen.com/.
Also, in what the teacher said, is the implied assumption that grammar teaching actually does work. There is no evidence that teaching grammar results in the student truly acquiring the grammar. A certain degree of retention is possible in the student’s conscious “monitor” (an internal editor), remembering some grammar rules, but this is limited.
Clearly grammar cannot be acquired in such a conscious way. One of my favorite examples of this, which I have brought out many times before is pronouns of gender (“he”, “she”, “his”, “hers”), a grammar rule that can be taught in ten minutes it is so simple but can take a student a year or two to master.
Grammar “teaching” doesn’t work.