Annotating linguistic data is often a complex, time consuming and expensive endeavor. Even with strict annotation guidelines, human subjects often deviate in their analyses, each bring different biases, interpretations of the task and levels of consistency. The aim of this paper is to explore a way to find out the inconsistencies in the corpus TreeBank which is used for syntactic analysis through the procedure we study the inconsistencies of verb phrase tagging in the corpus TreeBank. At the same time, we can analyze the inconsistencies of verb phrase tagging which are found in the corpus TreeBank in order that we can find a way to improve the consistency of verb phrase tagging automatically which is effective to improve the quality of corpus.