As for state schools only teaching rudimentary grammar when teaching languages - this is utter rubbish.

Like all pidgins, Russonorsk had a rudimentary grammar and a restricted vocabulary, mostly composed of words essential to Arctic fishing and trade (fish, weather, etc.) and did not particularly deal with unrelated issues (music, politics, etc.).

The captain spoke Nine Worlds trade lingo, a degenerate form of Sargonese, uninflected and with a rudimentary positional grammar.

Instead, structured gestural sequences, or syntagmata as MacNeill calls them, might already have had a rudimentary grammar before they were overlaid by speech.

Pidgins are significantly simplified languages with only rudimentary grammar and a restricted vocabulary.

Later on, Goodglass defined the term as the omission of connective words, -auxiliaries and inflectional morphemes, all of these generating a speech production with extremely rudimentary grammar.

I asked, aiming for the same rudimentary grammar and low accent voiced by the code.

Most were constructed in the Boasian tradition, one used by Boas himself in his rudimentary Tlingit grammar published in 1917.