Applications of Grammar Book 3

It contains errors and some of his analysis is not right. For example in page 141 ( adverb clauses ) he said : It is clear [that you not know the facts]. (clause modifies the adjective "clear" = not correct because according to his view the clause between the brackets = adverb clause and it is not so. It is a noun clause That you do not know the facts is clear. So , it is subject complement