Idiom is the syntactical, grammatical, or structural form peculiar to a language. Sentence structure determines syntactical relations and verbs are not conjugated. The inscriptions in Greek are full of spelling and syntactical errors. No further syntactical distinction is made between those in code. In syntactical borrowing, Spanish words are used in an English sentence structure. Roth and Dicke consider syntactical language an "intelligence amplifier". Tarski proved a stronger theorem than the one stated above, using an entirely syntactical method. This "extension" of the foreign class is purely syntactical. There are a handful of syntactical practices unique to Canadian English.