单项选择题______ refers to actual speech, the speech acts that are made possible by the system of the language.
单项选择题When did the first edition of the three-volume Encyclopaedia Britannica come out
单项选择题A linguistic study is ______ if it tries to lay down rules for correct behaviour.
单项选择题The national bird of New Zealand is the ______.
单项选择题The Adventures of Huckleberry Finn was written by ______.