Six groups, each consisting of 10 Ss, produced strings of 11, 22, or 33 words, under one of two sets of instructions: “structured” instructions which asked S to produce a grammatically acceptable string; “unstructured instructions” which solicited a random, unconstrained string. Each word in S's production was classified into one of six grammatical classes. For the structured instructions the rank ordering of frequency of the six classes was functors (40{\%}), nouns (25{\%}), verbs (13{\%}), adjectives (12{\%}), pronouns (6{\%}), adverbs (3{\%}). For the unstructured instructions the rank ordering of frequency was nouns (68{\%}), adjectives (12{\%}), verbs (11{\%}), functors (4{\%}), adverbs (1{\%}), pronouns (0.55{\%}). The findings were discussed in relation to three questions.
{"Write a random string, just as they come to mind. Do not use proper names.","Construct the sentence with whatever words come to mind, but do not use proper names. Use commas sparingly, but do not use semicolons, colons, dashes, or other punctuation marks."}