  In C-tests the hypothesis of items local independence is violated, which
doesn't permit to consider them as real tests. It is suggested to determine the
distances between separate C-test items (blanks) and to combine items into
clusters. Weights, inversely proportional to the number of items in
corresponding clusters, are assigned to items. As a result, the C-test
structure becomes similar to the structure of classical tests, without
violation of local independence hypothesis.
