Abstract: This paper aims to study the discourse features of the English double predicate from a cognitive-functional perspective.The research question is while the DP clause has acquired the conventional linguistic unit status, thus becoming part of the full schematic network of PredAdjSbj be PredAdj construction, why it cannot be a construction on its own? A study of 55 instances of the DP clause as random sampling is conducted, which reveals a number of specific discourse features of the elements of the nuclear DP clause that point to the two basic discourse features of the clause, namely, double in structure and specific in meaning in realizing the context in which it is used.The results are further confirmed by a study of 35 instances of the DP clause as systematic sampling, which brings to light the fact that these features are so comprehensive and so systematic that they can only be determined by the context and therefore may be regarded as traces of the context.As the discourse features stand out so prominent in the DP clause, it follows that the context should be readily inferable from the DP clause as part of the text.Two samples are examined and the results confirm the hypothesis, thus giving additional evidence to the discourse features as traces of the contexts.Further evidence is also provided by examining the repetition of some DP clauses that appear in a short span of discourse, which, due to their specificity in realizing the context, serve to highlight some severe social context.Finally it is pointed out that the discourse features of the DP clause are themselves limitations to the clause in its realization of context, each imposing a limitation on the DP clause, with the result that the DP clause is limited to one type of context to the exclusion of all others.The limitations on its realization of context means the limitations on its use in discourse.This is evidenced statistically by its rare occurrences in a novel and in a short story, which compare poorly with the occurrences of clauses ofPredAdjSbj be PredAdj structure.As the discourse features indicate, the DP clause retains so much of the context that it cannot be decontextualized enough to be a construction on its own.Saussure states that language above all is a means, an instrument(2006:120).The DP clause is a tool for special purposes in the linguistic kit, so it cannot be one for all purposes.That is why it cannot be a construction on its own.